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Do we really need an antivirus/anti malware apps for our android phones, if so what is the recommended antivirus or the best app for the job. (Free if possible).
Right now i'm using webroot basic and finding it very good and its free.
Hey
Not sure bout the one you mentioned but im using lookout seems good .
Anytime i ve read news of virus attacks lookout gets a mention for protection against it so reckon it must be good
Has been afew viruses in recent months so i def would use something.
Sent from my LT15i using XDA App
pushtostop said:
Hey
Not sure bout the one you mentioned but im using lookout seems good .
Anytime i ve read news of virus attacks lookout gets a mention for protection against it so reckon it must be good
Has been afew viruses in recent months so i def would use something.
Sent from my LT15i using XDA App
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Click to collapse
webroot has been trusted in the pc industry as one of the best anti spyware program. Also eset has just opened beta for their antivirus, tried it but didnt recognize the virus i,ve put through my phone unlike webroot. Also tried lookout, its ok thou it eats a lot of my memory, about 26 mb to be exact whereas webroot only takes up about 13 mb max.
Cool
Well ya kinda anwsered ur own question then webroot is best.
Just sharing my limited experience
Edit : been watching lookout over the last few hours and ram usage has hoovered between 6.5 n 6.8 mb
Which is far less than u stated and less than webroot at 13mb
Hope this helps
Sent from my LT15i using XDA App
I would recommend this one:
https://market.android.com/details?id=com.quoord.tapatalkxdapre.activity&feature=search_result
1) It doesn't hog your ressources
2) It has a wealth of information, including the relevant one that malicious code aka viruses need YOUR consent in order to run in Linux, thus making antivirus software moot
3) It doubles as an entertaining forum.
Logseman said:
I would recommend this one:
https://market.android.com/details?id=com.quoord.tapatalkxdapre.activity&feature=search_result
1) It doesn't hog your ressources
2) It has a wealth of information, including the relevant one that malicious code aka viruses need YOUR consent in order to run in Linux, thus making antivirus software moot
3) It doubles as an entertaining forum.
Click to expand...
Click to collapse
Does malicious code need your permission to run on android too? Is it always obvious that they are malicious or do they disguise as something one may want to download?
hmm i dont think anti virus is a need ..
Logseman said:
I would recommend this one:
https://market.android.com/details?id=com.quoord.tapatalkxdapre.activity&feature=search_result
1) It doesn't hog your ressources
2) It has a wealth of information, including the relevant one that malicious code aka viruses need YOUR consent in order to run in Linux, thus making antivirus software moot
3) It doubles as an entertaining forum.
Click to expand...
Click to collapse
LOL that made me laugh so hard.
pushtostop said:
Cool
Well ya kinda anwsered ur own question then webroot is best.
Just sharing my limited experience
Edit : been watching lookout over the last few hours and ram usage has hoovered between 6.5 n 6.8 mb
Which is far less than u stated and less than webroot at 13mb
Hope this helps
Sent from my LT15i using XDA App
Click to expand...
Click to collapse
weird i installed lookout and tried monitoring it for more than an hour and it always hovered in the 20's. maybe it was scanning or something, webroot now is at 5.1 mb in ram usage.
animboo said:
Do we really need an antivirus/anti malware apps for our android phones, if so what is the recommended antivirus or the best app for the job. (Free if possible).
Right now i'm using webroot basic and finding it very good and its free.
Click to expand...
Click to collapse
No. We dont need. What we need is to educate ourselves not to download virus.
i think KASPERSKY has also launched an antivirus too
try it
Hey
have tried webroot seems good similar to lookout cant test how they compare on virus detection but ui is similar.
Still cant understand why it zaps so much ram on u
I know ya have to give the virus permission to run but i ve heard they disguise as apps ya might know and trust so thats is why i use it .
Sent from my LT15i using XDA App
hierarchy666 said:
No. We dont need. What we need is to educate ourselves not to download virus.
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Click to collapse
What about the 30 malicious apps google removed from the market last week?? How we going to educate ourselves to not download malicious market apps? Anyway i use ALYac its a great free AV option
Sent from my R800i using Tapatalk
try lookout it is good and you can find your device if you lost it.
an alternative would be dr. web antivirus. this app is very good in scanning the whole system instead of just apps, however i uninstalled it and switched to lookout coz whenever my screen turns off during scanning it does not scan! However i am not sure if this bug still exists. Try both these apps and you come to a conclusion. Hope I hepled
Do I need to have some kind of Antivirus protection for my Thunderbolt?
I think they slow everything down on my Thunderbolt. If I do need it then
which one is the best that won't slow down my Thunderbolt.
Thanks in advance for advise.
I don't use AntiVirus because some of them do not like the fact that we are rooted and wont work with it. As long as you are smart with choosing your apps from the market you should be able to skirt around without the need of any AV for your phone.
Should you chose to use one tho I have heard good things about Lookout Mobile Security. Its more advanced features are not in the free version tho.
I don't use antivirus on my rooted Thunderbolt either and I'm pretty sure you will find that the norm amongst our userbase.
Its up to you I do cause i'd rather be safe than sorry but most will slow you down.
Driod security (avg) is the worst, eset is great and I don't notice any slow down on my driod 2, lookout is well fast
Trust me d-..-b im from the webs
Not needed if you pay attention and understand what you are doing.
Antivirus apps are not valid replacements for caution, understanding, and a little sense IMHO.
I'm curious how many actually use an antivirus on there phone and if so which and why I've used lookout and anti-virus free but I'm looking for a battery efficient app that actually does its job properly all the time thanks for any input
My opinion, they're generally worthless, battery killing, problem causing programs.
The only good thing about lookout is the lost phone feature, which can be done with far better apps that are designed just for that.
Sent from my DROID X2 using XDA Premium App
juhde said:
My opinion, they're generally worthless, battery killing, problem causing programs.
The only good thing about lookout is the lost phone feature, which can be done with far better apps that are designed just for that.
Sent from my DROID X2 using XDA Premium App
Click to expand...
Click to collapse
Just dont download sketchy stuff
slowz3r said:
Just dont download sketchy stuff
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Click to collapse
Seriously. No anti virus will protect you from everything. And I think it is worthless for phones at this time.
Awesome info and since getting the dx2 I haven't had one or felt the need on my fassy I tried others and never felt like it was doing me any good so I was curious I don't feel the need for one other then outside/3rd party apps is there a safe way to work threw those type of apps thanks
The best thing you can do for security is make sure you don't have any networks stored as netgear or linksys because if it finds that network in a public place it will connect to it and someone can packet sniff your passwords
If you are going to connect to a wireless network in an airport, always ask someone what network is the airports, people can set up laptops or cell phones for the purpose of tricking people to connect to them so they can packet sniff you
http://www.blog.jbi.in/security/firesheep-a-packet-sniffer-that-creates-security-nightmare/
Sent from my DROID X2 using XDA App
I used lookout which actually checks each apk to make sure that the should aren't known culprits.
Running a mobile phone with android without anti-virus protection is asking for trouble. Would you run your home machine without it? Android malware has picked up 300% in the last 4-5 months with rootkits and all sorts of nasty things coming down the pipe. Here is a site with some of the more recent stuff listed for androids: http://community.ca.com/blogs/securityadvisor/default.aspx
I've ran lookout, avg, and kaspersky mobile so far and have had 2 instances where lookout and kaspersky reported issues with software upon installing.
A rundown of what's out there and some reviews of them would be wonderful but I haven't come across a site with it yet. If someone else has please chime in...
On my windows machine i have one, on my linux system i don't,, on my android (linux) phone? Not a chance, make sure your permissions are alright, use your head keep a nandroid backup and you don't have to worry
Oh and on your link there the only "scary" thing said specifically that it was for windows based systems
Sent from my DROID X2 using XDA App
PnoT said:
Running a mobile phone with android without anti-virus protection is asking for trouble. Would you run your home machine without it? Android malware has picked up 300% in the last 4-5 months with rootkits and all sorts of nasty things coming down the pipe. Here is a site with some of the more recent stuff listed for androids: http://community.ca.com/blogs/securityadvisor/default.aspx
I've ran lookout, avg, and kaspersky mobile so far and have had 2 instances where lookout and kaspersky reported issues with software upon installing.
A rundown of what's out there and some reviews of them would be wonderful but I haven't come across a site with it yet. If someone else has please chime in...
Click to expand...
Click to collapse
If you don't instal shady software, you won't have a problem.
Sent from OH MY GOD IS THAT A SQUIRREL!
juhde said:
If you don't instal shady software, you won't have a problem.
Sent from OH MY GOD IS THAT A SQUIRREL!
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Click to collapse
You're seriously naive and have no clue about being security conscious in this day and age.
Google took down a ton of applications from its own appstore because of being infected with malware and then some more later on that contained a rootkit. Did any of those application fit your definition of "shady"?
The world as we know it is not a rosy place to shrug off protecting your investments and hard earned cash. If you chose to be that way then so be it but giving bad advice is not smart.
P.S. I have some swamp land in Florida I'll sell you CHEAP so send me some $$ to my payal account and I can forward you over the details after payment is made.
PnoT said:
You're seriously naive and have no clue about being security conscious in this day and age.
Google took down a ton of applications from its own appstore because of being infected with malware and then some more later on that contained a rootkit. Did any of those application fit your definition of "shady"?
The world as we know it is not a rosy place to shrug off protecting your investments and hard earned cash. If you chose to be that way then so be it but giving bad advice is not smart.
P.S. I have some swamp land in Florida I'll sell you CHEAP so send me some $$ to my payal account and I can forward you over the details after payment is made.
Click to expand...
Click to collapse
You're the naive one, I've been running android for nearly 3 years and never had a single problem, because I don't run around installing crap just because it looks cool. You obviously do since your super cool and necessary anti virus apps have found at least 2 problems in your phone.
Sent from OH MY GOD IS THAT A SQUIRREL!
They Couldn't Hurt My Credit Score If They Took My Information, Actually They Might Improve It For Me.
First of all, android is linux base so there are no viruses known to be around. If you want a battery management, then I suggest using Juice Defender Ultimate.
Sent from my DROID X2 using XDA Premium App
Furioustylez said:
First of all, android is linux base so there are no viruses known to be around.
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Click to collapse
ROFL
Edit : that guys other posts are just as hilarious and uninformed
Sent from my DROID X2 using XDA App
I highly recommend LBE Privacy Guard as an extremely useful security tool. It will classify your installed apps in three categories, Untrusted, Trusted, and System. Any app you are unsure of you keep its default Untrusted status, and you can edit it's custom profile to disable any privileges you see fit. Just got a Cartwheel counter app you are unsure of and it requires internet and identity info to install? You simply edit the LBE profile after installing to disable the app's access to internet, etc. Any time an untrusted app tries to use a permission a simple pop-up appears with an allow/disallow. This action can also be set as default for every time the app calls on this function. Very robust, highly recommended, and COMPLETELY FREE.
That said it might not do anything to protect from the more advanced malware that might be out there, but is a great defense for the more simple ones.
Just no. Seriously.
Sent from my DROID X2 using Tapatalk
Furioustylez said:
First of all, android is linux base so there are no viruses known to be around. If you want a battery management, then I suggest using Juice Defender Ultimate.
Sent from my DROID X2 using XDA Premium App
Click to expand...
Click to collapse
That is wrong. There is malware for android because it has become so popular, and it is designed to be simple but it gives the apps more control.
Honestly, I used to use one but since I read ratings and am stingy about what I install, I figure I am fine.
When they say "malware", its referring to apps that steal your personal info. So like I said there before, no viruses for linux base products.
Sent from my DROID X2 using XDA Premium App
Hate to disagree with you but the proper definition of malware is:
mal·ware/ˈmalˌwe(ə)r/
Noun: Software that is intended to damage or disable computers and computer systems.
Now, there most definetely is malware for android. You just have to be conscientious of what you install.
Hello to everyone!
Maybe it's a stupid, noob question, but I googled for this without success.
And even a search in these forums was not helping, so... let's start!
It's saturday morning here and I start my weekend in one of the most disappointing ways...
Some minutes ago, my Galaxy Note showed a red icon in the status bar. I checked it, and it was Zoner antivirus. Hooray!
The malware that it found was exploit.AndroidOS.Lootor.A, and I don't know what it is, but it really sounds bad.
The disappointment went worse when I discovered that the malware (according to this antivirus) was in the latest Superuser update. Something I'm not going to uninstall without thinking twice.
What should I do? I think I'm going to follow my elephant-phone's suggestion and uninstall the update, since it's telling me that I can use "the original version" (at least, in Italian the message I see means literally that).
If you tell me -as I think- that it is just a false positive, I'll be happy to reinstall any update, but anyway I am asking for the opinion of more experienced users.
Thanks in advance!
PS: while I was writing here, there were some evolutions in this problem.
I followed the instructions and uninstalled some update (or at least the phone told me so).
Now it seems that Superuser should be uninstalled because it has inside
exploit.AndroidOS.GingerBreak.A
HELP!
I'm not going to uninstall superuser (I think I couldn't anyway), but I am worrying now!
PPS: ok googling exploit.AndroidOS.Gingerbreak.A I found that it is a false positive, so I assume that also exploit.AndroidOS.Lootor.A is safe... but I still would like some confirmations, I am quite new to Android and this is not the way I want to learn lol.
Virus scanners on android truly are pointless. They will pick up anything that changes the root permissions llike Super user or the root exploit. As long as your not using apks from iffy sites like 4shared or something you will be fine.
So how can we solve that?... I found a couple of apks on APPLANET that lead to a GAME CASINO on real market... Strange but that´s look like a virus to me...
Thank´s in advance.. Cem..
Don't use applanet unless your begging for a virus or to have your phone make calls to long distance numbers and send texts to paid account. Also no one on XDA will help you with any black market app markets.
zelendel said:
Virus scanners on android truly are pointless. They will pick up anything that changes the root permissions llike Super user or the root exploit. As long as your not using apks from iffy sites like 4shared or something you will be fine.
Click to expand...
Click to collapse
I'm not expert enough yet to discuss your point, it just seemed weird to me since it is the very first problem I had with an android anti-malware software. I've run Superuser for something like two months without any warning...
Anyway it's solved now, even if not in the best way. Something messed up in my beloved phone when I rebooted it one moment after my last post... I had to re-synchronize all my accounts and to reinstall most of my apps, it seemed that my phone lost all app data.
Now it's ok (luckily, I've learned enough 'til now to bring it slowly back to normal) but the procedure was painful.
Great lesson here: wether you consider antimalware useful or not, don't rely on it more than on good ol' common sense!
PS: anyway, why are they pointless? Aren't they able to find possible problems? I've recently learned that "possible" problems aren't necessarily problems, but it seems strange to hear that they are useless... just an explanation please.
Always good to have a virus scanner on you're android mobile. Even i've you only downloading wrom the market it can be infected (Very small change). Nothing is secure in this world. Better to have protection one time to much then to have it to late. How more popular android is going to be, how more change you can have for infections. Even its still low. Lookout cost nothing and says nothing about my superuser and other rooting apps. I use it on my tablet and phone and it works great.
Recently read a test and no Antivirus App was able to find more 15% of the Viruses, plus they always slow my phone down.
Best solution for me is being cautious and checking permissions.
Sent from my HTC Desire using XDA App
i think it might be a good idea for all that root their devices to first understand the concept of a false posotive virus scan result
also it may be worth understanding that from anti virus software standpoint any alteration to system safety may be undesirable as its designed for the end user who doesnt even know what root is ..
increasingly android caters for 2 markets, the sort of people who come here and probably own about 30 devices including pcs tablets phones etc and love tech.
and the other market of people who own a pc with xp on it and one phone, only running android because thats what the salesman sold them - and not because they insisted on Android.
terminal 7 said:
i think it might be a good idea for all that root their devices to first understand the concept of a false posotive virus scan result
also it may be worth understanding that from anti virus software standpoint any alteration to system safety may be undesirable as its designed for the end user who doesnt even know what root is ..
increasingly android caters for 2 markets, the sort of people who come here and probably own about 30 devices including pcs tablets phones etc and love tech.
and the other market of people who own a pc with xp on it and one phone, only running android because thats what the salesman sold them - and not because they insisted on Android.
Click to expand...
Click to collapse
Oh I have to agree. Too many people get Android because its cool and then they root because they think its cool. They should understand what they are doing before they make a choice for the OS on their phone.
If you think running Linux is too much trouble to run and keep up on your computer why would you run it on your phone when it takes just as much to keep up?
terminal 7 said:
i think it might be a good idea for all that root their devices to first understand the concept of a false posotive virus scan result
also it may be worth understanding that from anti virus software standpoint any alteration to system safety may be undesirable as its designed for the end user who doesnt even know what root is ..
increasingly android caters for 2 markets, the sort of people who come here and probably own about 30 devices including pcs tablets phones etc and love tech.
and the other market of people who own a pc with xp on it and one phone, only running android because thats what the salesman sold them - and not because they insisted on Android.
Click to expand...
Click to collapse
Yes, but you know, I had the naive hope that an antivirus for Android should check if an app is going to do a bad use of the permissions I give to it.
I.E. : I see a game that requires internet connection for multiplayer. It's ok, isn't it? In a perfect world, an antivirus should check if that game is going to connect to its multiplayer server or to a bad one... (it's just an example, I think that important brands aren't likely to lose their reputation that way)
Anyway, would you suggest me to give Avast a try? At least, I've seen that it has decent anti-theft features...
Max Morden said:
Yes, but you know, I had the naive hope that an antivirus for Android should check if an app is going to do a bad use of the permissions I give to it.
I.E. : I see a game that requires internet connection for multiplayer. It's ok, isn't it? In a perfect world, an antivirus should check if that game is going to connect to its multiplayer server or to a bad one... (it's just an example, I think that important brands aren't likely to lose their reputation that way)
Anyway, would you suggest me to give Avast a try? At least, I've seen that it has decent anti-theft features...
Click to expand...
Click to collapse
Please receive this feedback as intended, respectfully and well meaning...
if your finding yourself having concerns when an anti virus flags up your rooted status and yet you still feel the need for an anti virus package i suggest you un-root and keep to a stock kernel - this way the anti virus software will inform you of any possible intrusion or system change.
if however you must have root i think you need to simply come to understand more about what the anti virus packages can do .. or actually what they are limited to doing - might i suggest spending some time learning about a popular linux distribution too as it will bring about a different frame of mind and then you will realize that the anti virus software flaging SuperUser as a virus is actually neither true or a false posotive .. its just working from a different set of perspectives to that of a confident root enabled computer user .
i hope this makes sense without coming across in the wrong way, i just really think people should learn from XDA and the devices they buy & come to XDA for help with .
Respect the info found at XDA -and its users, we all learn together here
.
No malware in superuser app. Proceed
sent from an HTC sensation on CM7 alpha #10
super user by chainsdd has been around for a long time. and was developed to make being rooted easier, a lot easier. it gives you control over all files on your device. the developer is very trusted. no worries
Sent from my Transformer TF101 using xda premium.
Thanks to every single user that chose to spend some time for this post.
I was kinda sure that Superuser had to be safe, but lack of experience made me fear that somehow I could have downloaded the wrong package, or something...
The weirdest thing, is that Superuser and antivirus have been there together for a while, so I wondered what on earth was happening.
Well, I've done a mistake and now I've learned something... it's ok.
terminal 7 said:
Please receive this feedback as intended, respectfully and well meaning...
if your finding yourself having concerns when an anti virus flags up your rooted status and yet you still feel the need for an anti virus package i suggest you un-root and keep to a stock kernel - this way the anti virus software will inform you of any possible intrusion or system change.
if however you must have root i think you need to simply come to understand more about what the anti virus packages can do .. or actually what they are limited to doing - might i suggest spending some time learning about a popular linux distribution too as it will bring about a different frame of mind and then you will realize that the anti virus software flaging SuperUser as a virus is actually neither true or a false posotive .. its just working from a different set of perspectives to that of a confident root enabled computer user .
i hope this makes sense without coming across in the wrong way, i just really think people should learn from XDA and the devices they buy & come to XDA for help with .
Respect the info found at XDA -and its users, we all learn together here
.
Click to expand...
Click to collapse
This was interesting.
First of all, I am not offended at all and I don't understand how I could.
Well I could probably live without root (except for a couple of useful apps)... but I'm not going to un-root it for now.
I am a sturdy guy and I want to learn everything (everything I am interested into, I mean) about this OS. Trying and trying again, at the cost of some little problems if needed.
As for Linux, almost all my PCs have also it inside (win7 mostly for games), and I have never had a problem worth this name when using it. Never had something like an antivirus there, just some common sense and everything was fine.
I think I should have the same attitude towards Android as many of you have suggested. And I am willing to get some more info about android's antivirus limitations. Just because I'm curious.
Can you suggest some particular post here in xda?
Thanks again!
Please use the Q&A Forum for questions Thanks
Moving to Q&A
Hi Guys,
We know they exist, we get warnings in the news and on internet but I never met anyone who had a virus on his/her phone. And I live in China (Shanghai) with 30 Millions people. I'm starting to wonder if it's really important to have an anti-virus app. Of course wisdom tells me it just need one virus to make it worth. But with all the crazy phone people that are here, there must be someone who had a virus at some point. If so, what kind of virus? How many? And do you think an Anti-virus app is really necessary? Are you using one? Are you wearing condoms?(Whoa forget that last one, too many questions.)
I don't have one for the moment but maybe after reading your comments I'll get one. Will see.
I personally dont use one. Antivirus can (should) detect mallitious apps that might take advantages of user permissions and send sms, call someone or steal personal info without notice. Also almost all antivirus solutions offer anti theft protection (not so useful as it sounds).
My oppinion is that they are not worth the ram ussage if you are not installing free cracked apps from unofficial sources which is the most common place to install malicious app by mistake.
Sent from my GT-I9300 using xda app-developers app
No. I don't have any anti virus apps too. I feel it is unnecessary.
Sent from my GT-I9300 using xda app-developers app
Using smartphones for 10 years.
never needed oe used an antivirus program (except one occassion, to briefly see its features)
So any of you know someone who had a virus?
Sent from my GT-I9300 using xda premium
Had once in symbian Commwarrior.A but never installed virus soft.
Sent from my GT-I9300 using Tapatalk 2
I don't think I need one! I don't do online banking from my phone! Other than that It will slow down the phone unless you are not doing something dodgy.
I put an Anti Virus on my first Android phone as I fell for all of the scare tactic bull**** companies give you to download their products, but no, I don't on my S3 and never have. If you ask me and probably half of the XDA members, most Android "viruses" are non existant, and are mentioned to scare you into buying their products (most have a paid version that will "scan better"). As a matter of fact I've researched it quite a bit and only came across 2 legit Android viruses, both of which are from illegally downloading APK files from a non-google site.
So to answer your question, unless you download apps illegally, you're fine. Only Android security I spent money on is Cerberus Anti-Theft, it's really good should you get your phone stolen. The only downside is that you have to either have Data or WiFi on 24/7 so if it does get stolen you can access it from the control panel, but there is sadly no other way. Just make sure if you do spend your hard earned dollars on it that you get Titanium Backup or another equivalent so if you wipe your phone you don't lose it.
blackyz said:
Had once in symbian Commwarrior.A but never installed virus soft.
Sent from my GT-I9300 using Tapatalk 2
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Click to collapse
Interesting, symbian is not as popular as Android.
What was the virus doing? I mean was it calling people or sending sms to your contact?
no, other that stealing nothign they could do,
but my visa is prepaid and my birthdate is senstive info.
Oh my... of course I have an antivirus app for my phone. In fact I have 10. My phone needs virus protection inception. If I don't have at least 5 antivirus apps on my phone, I won't feel remotely safe.
I typed this by hand.
Techniques said:
I typed this by hand.
Click to expand...
Click to collapse
It's ok I can read by eyes.
I've been using avast for about 3 months now, having picked up anything, all about preference tho if you feel safer with it then just get one
I've never had antivirus, it just uses way to much CPU, RAM and unnecessary storage on your device. My phones never played up or messed up. I think its just a money making scheme tbh. It slows your phone down and is definitely not needed
Sent from my GT-I9300 using xda premium
no, and i think it' not necessary an antivirus
if you know what you do you don't keep virus .... IMHO
Just be careful which apps you're about to downloa - don't install fart-soundsboards for example.
I use Lookout Mobile Security but mainly for the remote locate feature. It's free for up to two active phones in one account (account is tied to your e-mail).
Never had it report a virus though... don't think it hurts and never noticed it slowing down my phone, not even my previous HTC Desire
Eh, I ran Lookout when I first got an Android phone, but I don't think it ever accomplished everything other than introducing a slight delay after installing an application. I do run the JB-compatible version of LBE (which includes a ton of bloat - including an anti-virus), though, as I do like to block permissions, but I'd switch to PDroid in an instant if it were available for TouchWiz ROMs.
i think AV is useless on the phone.
had avast for sometime (got "scared"), other from a little battery drainage didn't feel slower or anything.
removed it to check battery stats without it and just figured it's useless...
as for anti-theft, you get apps that do just that, so no need for AV for anti-theft security.
Depends how confident you are as a smartphone user. If you check your app permissions (or if it is from a reputable enough dev), you shouldn't have any issues. As has been said above, cracked apps are the most dangerous, so be extra careful with those!
Also faik apps can't run hidden on android... so if you are an advanced user you should be able to check with a task manager what apps run in the background. If it isn't running in the background (and isn't your keyboard), then I doubt it can log your keystrokes etc.
So yeah, I don't use one. If phones get powerful enough such that the performance/battery impact is un-noticable, I'd probably install one (as I do on my PC - nod32), even though android is a more closed environment. If you're a noob who installs tons of cracked apps though (p.s. I'm not saying these attributes are necessarily linked lol), then of coure you should use one.