How often do you upgrade your phone?

My current (Android, custom ROM that still gets updates) phone is 6 years old. I tend to upgrade when the phone breaks, the battery gives up, I hear of some severe vulnerability, or even these updates stop. As a replacement I get something used in the $100-150 range, so at least a couple years old. Maybe every 5 years or so.

Edit: The power bank is my friend.