There are plenty of decent cycling and hiking computers on the market these days. Care to make a custom one on your own? HikeBuddy has you covered. It is a hiking/biking computer development board based on ESP32 that can be used to make an outdoor GPS tracker. It has a low power LCD display, various sensors and Bluetooth.
This hiking dev board has a 2.7″ display. It has a GPS module, a temperature, pressure and humidity sensor, and an accelerometer/magnetometer. It has Bluetooth and WiFi for adding more sensors and data transfer.[where to get it]