[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.