Well, it's seems to me a complete nonsense: you will destroy your battery just to make some cents...
It would be the same as to dig for gold with a spoon...

Do not forget that the smartphone is not physically designed for long-term load! Passive cooling does not provide sufficient heat sink, as a result, there are a number of problems. From the banal damage to the battery, to putting up the display module, or latent degradation of system on a chip.

This look interesting... I'll try to understand something about, and - if I succeed - I'll give you a feedback.
And the fact about "hidden mining" is actually irritating.

Hmmm. Not really. I'm kinda skeptical about mining crypto using mobile phone. Besides the reason that I don't want to waste my mobile phone's space and capacity, i'm also worried of my phone's privacy. Plus i don't want to buy multiple phones just for that mobile mining.
I prefer Master nodes though. 

 If you do want to give Bitcoin mining a try on your Android, there are a number of apps you could check it out. As always with any Android app, use these at your own risk as Google does not verify the safety or security of Android apps on its Play Store.

I doubt that there is a crypto that can be mined by a mobile device and even if there is it will not be profitable regardless of the mobile devices specs because it will always be a fraction of a GPUs raw performance. Also the mobile device would only overheat because of the stress and heat that the hardware will do while mining.

Our upcoming project will support mining on the mobile phone. As we are using the enhanced version of Delegated Proof-of-Stake Consensus algorithm, it takes almost no power to process the delegate round on nowadays smartphone. The only thing we are concerned is that when the network is scaling, the block size as well as block time increasing may pass beyond the mobile phone capability. Still, when we launch the network, it still comes with the mobile mining application. We will announce this project soon in Bitcointalk, so stay tuned for us.

MINING isn't possible on cell phones it requires rigs maybe in the future  it is possible

Yeah im pretty sure electroneum is beta testing this and will launch soon but i dont think youll get rich with your s7 mining