I down loaded urban biker app this week I have made one ride with it . The cheap ( schwinn ) Wired computer on my bike showed 16.4 phone showed 16 miles I am guessing the gps will be closer to the Actually mileage ??
I usually ride 8-20 mile trips,
All I want is
trip distance
Average speed
Odometer
Altitude and max speed are interesting but not needed
I ride bike trails and known roads so mapping isn't a need
My concern is battery life , I am guessing that not running the app screen will increase this
Plus I have battery bank chargers
My thought is I can pick up a top tube phone bag just run my phone on all my bikes and have less devices. Also with different profiles the phone will cover all my bikes and have the same device measuring miles (consistent mileage across all bikes )

If my assumptions are wrong feel free to point me in the right direction and or point out a simpler or less power consuming app
Roy