A - Airplane mode on the phone has nothing to do with GPS. Airplane mode just turns off the cellular radio. The GPS receiver in your phone does not care about airplane mode. Here's an explanation of what airplane mode does on a phone:
https://www.businessinsider.com/guid...rn%20off%20GPS.
"Depending on the phone model and OS, airplane mode may disable Wi-Fi and Bluetooth, but it won't turn off GPS."
B - Using the phone for navigation consumes negligible additional battery life. It sounds like you are imagining the phone being mounted to the handlebar and displaying continuously? No. You look at the phone, remember with your brain where you need to go, repeat every hour when you have reached the limit of your memory. Unless your memory is for some reason absolutely terrible, you should only need to look at your phone occasionally, especially if you're touring which means you are riding in the countryside. We're talking about a few minutes of additional screen time per day. A modern phone can play video continuously for 10+ hours. A few added minutes in Google Maps is a drop of water in the ocean. It does not affect your battery longevity at all.
C - Not sure what you're trying to get at with the comment about chargers. Everything can share the same charger nowadays. It's all USB.
D - Option 1 is lighter than Option 2. Option 1 has a phone and a charger. Two items total. Option 2 has a phone, a separate GPS unit, and a charger. Three items total.
Originally Posted by
fishboat
Not grasping the logic here (no need to explain it).
Option 1):
> use the phone for navigation,
> it pulls lots of power to do so,
> phone may well be low or out of power when/if needed as a safety device or to call for help(injury, significant mech breakdown, weather forecast/tracking, crime..)
> best to carry a backup battery bank(a heavy, extra "gadget")
> need to carry a charger and USB cord that charges both devices
Option 2):
> reserve phone as nav backup,
> phone set to airplane mode or turned off when not needed, phone battery in good shape when/if emergency arrives, severe weather tracking, simple text communication
> use cycling(or hiking) gps for navigation that's designed for use with long battery life
> skip carrying a heavier battery bank
> carry a usb charger and cord that charges both phone and cycling gps
Same number of items carried in both instances. Second option is lighter in weight and with better tools for the jobs at hand.
I choose door number two.
You do you..doesn't matter to me.