[raudette]

Mounting a modern phone to a bicycle will damage the cameras - they can’t handle the vibration - see https://support.apple.com/en-ca/102175

I have an iPhone that I believe was damaged in this way.

So you’d probably want a purpose built bike computer, an older phone that you don’t care about the camera, or perhaps there are fancy vibration dampening mounts that could work.

[mbirth]

Another way would be a CarPlay/AndroidAuto screen. These are available for cheap from e.g. AliExpress and can run off a power bank. This way, the phone does all the processing but can stay safely in a bag or pocket as all the display and control is done via the CarPlay/AA screen.

[kjkjadksj]

Waterproof? Able to sit in uv light all day without fouling the screen or melting the internals?

[mbirth]

Yep, there are models specifically made to be permanently mounted on a motorcycle. I’d hazard a guess that they’ll work just as fine on the handlebar of a bicycle. You’ll just have to waterproof the power source then, e.g. wrap the powerbank in a ziploc bag or tupperware container.