Forget using a smartphone to track rides when doing proper milage (although I would have thought the battery would last longer than ~40-50 miles, how long does it take you?)!
Garmin Edge 200 if you don't mind not having HR or Cadence data, Edge 500 if you do!
There are now those Bryton things which are also pretty good and a bit cheaper than a Garmin.
Forget using a smartphone to track rides when doing proper milage (although I would have thought the battery would last longer than ~40-50 miles, how long does it take you?)!
Garmin Edge 200 if you don't mind not having HR or Cadence data, Edge 500 if you do!
There are now those Bryton things which are also pretty good and a bit cheaper than a Garmin.