GPUs for BTC mining? Think again...
1 Bitcoin mining these days requires a specialist GPU-based rig to get anywhere and is way beyond the productive capacity of ordinary computers, much less smartphones. CoinKrypt is the digital equivalent of a gold rush claim jumper, according to Lookout.
Bitcoin has moved well beyond the days of being able to do any useful mining with GPUs. BTC mining is now well and firmly ASIC (Application Specific Integrated Circuit) only.
It can still be profitable to mine other alternative coins with GPU based rigs - which you then exchange for BTC in order to spend or cash out. Typically you're looking at around a 40 - 50 day return on investment buying a mid to top end AMD card after which the profit begins. That said you'd need an awful lot of them to make any real money.