Exactly. I carry two phones - feature phone for, you know, calling people, and a smartphone for its apps (perpetually in airplane mode). The bonus is that if I

Exactly. I carry two phones - feature phone for, you know, calling people, and a smartphone for its apps (perpetually in airplane mode). The bonus is that if I happen to run out of battery in feature phone (which still happens, though rarely), I can still stick my SIM card in a smartphone. Also, both phones last much longer this way.