How do I know 360 Security antivirus app really works? I have an Alcatel one touch fiercexl &amp; 360 Security is the antivirus/cleaner app I have. I'm  not entirely sure it even works like it says it should. Aft I use it &amp; leave the app, and then go right back to it, it seems like (almost always) it'll have just as much (if not the same) things to do. Like Clearing cache, cool down battery, boost,  etc. Also if I get a message that says"warning your alcatel has viruses, &amp; You have to do an antivirus scan before phone is damaged" it always says phone is secure no viruses detected. Then why did I get the message in the first place?  Is it also fixing the problem while scanning? Also why doesn't cleaning junk also cover app cache? It makes you do it manually in advanced clear. How do I know if it is actually working correctly or if I need a different antivirus? Can you recommend one for me if I need it?
First, That app is shit ! 
Second, It does nothing but clearing junk and cache of the apps on your device.  
It will always prompt you with ads and unwanted bullshit. 
There is no such thing as virus in your phone. If it were then it will make you almost impossible to operate your phone as the malware and torjans designed these days are pretty cool.

 Clearing app junk and cache is now a built-in feature in android. 
The memory booster does nothing but killing all the running apps in the background. Friend! My advice is to un-install that app ASAP !! save some memory than having an useless app