I've read about this news lately seems like samsung is trying to give life again to older phones by using them in creative ways such us security cameras and bitcoin miner (grouping 40 phones S5) that run on a custom OS not android. Personally I don't think it's enough to mine but  there is this picture that describe the power of those 40 phones grouped toghter : https://i.imgur.com/zeg7tc5.png