Mostly apps you'll find for mobile devices are faucets, some are paying, some aren't. Mining isn't really profitable from a phone or tablet, will cost you more energy than what you'll earn.
I use an application called grabpoin that is able to provide me free Bitcoin without the need for bother because I just download the application and do the task then bitcoin free as much as 0.01 BTC will go to my bitcoin wallet address
0.01 btc a day? Really? Already been paid from this application?
Sounds amazing right? But i do assume he do make an investment on a cloud mining because nothing on this world which an app would generate you bitcoin unless if you do make use on asic miners on mining it then it would be possible but on apps either on launching it on a pc or mobile phone then its not possible and for those people who do claim that it does work then its a total fraud or just simple a cloud mining app or something.