Better start a kickstarter or something to collect enough funds to build true open source mobile operating system. Someone will reply that's impossible, but I say it is just a matter of keeping scope small. Basic OS, few most important apps - phone, sms, maybe calendar or alarm, and let users build everything else themselves.
"Your App Should Have Been A Website", and banks at least in EU are providing open banking API, so it should be doable. More incentive for everyone to build APIs again.
