^ if you tried to pull 500h/s "in the background" youd shorten battery life to like 1 hour

And not just mobile connection, but changing connections (WiFi handoffs, moving between towers or in and out of service)

Maybe if they all ran on 1 core in lite mode pulling 5h/s on every android phone in the world (maths? I didnt do)

hmm not that we should be discussing the whole how to build effective malware for android... but could have the miner run only when the device is on charge (which for most people I imagine is about 10 hours overnight (then the heat could be hidden by the charging aspect)

No