In the age of digital technologies, everything develops at the speed of lightning. This is especially seen in devices, where even the coolest and newest device turns into something only a little bit better than a calculator. Most of us have our own device cemetery somewhere in the closet or elsewhere.
Therefore, it is quite a hot-button issue to turn them into something new, in order to make this junk useful again and maybe even profitable. That’s what Samsung did.
Read the full article: https://coinidol.com/samsung-turned-smartphone-into-bitcoin-mining-rig/
I doubt if they will be able to be successful in contributing any hashing power, using phones. When computers and GPUs have been rendered ineffective by ASICs, what can the processing power of old phones do?