alt Hacker Newsno, I mean I saw multiple companies at this point with their entier K8S cluster... is smaller than single new macbook pro :/
now, if you have 100,000 users with latest iPhone, say you use 10GB RAM in each, using A16 chip with 1.9 TFLOPS, each with 5G connection
this is 1 Peta-Byte RAM + 0.25 Peta-FLOPs GPU + 4 TB / second bandwidth
at zero cost (no-upfront, no-maintenance, users pay for, upgrade, and maintain their phones working, pay for internet, charging with electricity, cooling? - thanks!)
... it goes even wilder if you use macbooks
... and if you consider say mid-size town in China with population of 15 million, you go Exa-scale
and consider that for now iPhones are just sitting idle. for now.
Things don't work like that.
First of all iPhones have more like 6-8GB of RAM, 1-2 of which are already taken up by the system and system apps. Add some resident apps and maybe 1-2GB are already taken. Then of course during peak times, which are predictable but not guaranteed, 5-10% is maybe available. So out of your 10GB estimated per device, you actually average maybe 3GB.
Similar story for the CPU and GPU.
Then, availability: dead battery, no cell reception, airplane mode, etc, etc.
And on top of that, in the context of battery charge and long term wear and tear, you're assuming people will just let you run Bitcoin mining nodes on them.
You need a really solid incentive for people to loan you end user computing power for legitimate reasons.