There is no currency that is worth mining on a smartphone, you can get electroneum but it's not worth wrecking your phone for. It would be better to simply download an app and use it for trading coins instead.
not too sure about this but for electroneum case, it's not really mining on the phone right?
not 100% sure..
No, in the Elecrtroneum case the mining is happening on a computer remotely liked, the phone isn't mining itself.
It is probably more of a marketing gig