XuanWheel is an awesome product for bicycle. Your bike will become a colorful screen with the XuanWheel and XuanTail.
This App is a tool to help you play with the XuanWheel . You can not only send the picture we provide to the XuanWheel but also display the image created by your infinite imagination .
This app can also be a Monitor, it can show the speed , cadence ,heart rate, average speed ,etc.

Continued use of GPS running in the background can dramatically decrease battery life.

GIF Instruction:
https://youtu.be/_s5vmEFb8Lc
https://www.bilibili.com/video/av13266294/