Ask HN: Smartphone as a Bike Computer Replacement?

This really surprised me... cyclists will _regularly_ spend $400+ on a cycling "head unit" that is just a dumbed down smartphone to give them turn-by-turn directions, record data from sensors, and work as a HUD.

The only advantage of a head unit is they have an ANT+ radio, which is a superior protocol than BLE for data gathering. Nowadays, nearly every sensor has dual mode BLE/ANT+.

Shimano has ETube Ride, which is about the closest thing I can find to a replacement, but it lacks a critical feature to be able to import a route. It does connect to BLE speed/candence/DI2 transmission however, but does not connect to a BLE heart rate monitor ironically.

Other apps like Strava will do routing, but only connect to BLE HeartRate sensors, and don't connect to speed/cadence/DI2 (electronic bike transmission).

It seems like nobody has the whole package. Am I missing something? Just seems like an obvious hole in the ecosystem a startup should have filled by now.