Carrying an expensive phone on the bars is not the best of ideas. Some people use an inexpensive smartphone for the purpose. As for me, I went through too many damaged phones to do it again. My answer is a GPS bike computer on the bars:
- Great battery life
- Invulnerable to crashes
- Can be used in any weather
- Does workout monitoring, GPS navigation (with climb information), and workout registering.
Garmin, Wahoo or Karoo2 integrate with Specialized and Giant e-bikes. I carry my smartphone safely tucked in the back pocket of my jersey.