It all started as a simple telemetry system for my motorcycle but quickly turned into a more generic GPS tracker and logger that can be used to log the tracks and related statistics on SD card.
The Nextion display shows some information in real time, the complete list of available information can be found on the GitHub page.
It is possible to navigate through the pages using the buttons at the bottom of the display. The main issues with the Nextion display is that it is not readable under direct sunlight, it has a limited flash memory (16Mb) and it's not suitable for rendering complex custom graphics such as charts because the UART it's too slow. I am planning to replace it with the reflective JDI LPM027M128B display, which is perfect for bright environments. It doesn't have any backlight panel so the power consumption is very low but it's not touch screen.
I am also planning to replace the great u-blox NEO-M8N gps module with the even better and more recent NEO-M9N. Integrating the Nordic Semiconductor nRF52832 for reading the heart rate measurements and other ANT+ sensors and add a barometric pressure and relative humidity sensor.
Supports three different logging modes: time, distance and auto (not implemented yet).
The final ambitious goal is to replace the teensy with an MCU because I would like to create a completely custom PCB.