Skateboard Speedometer, bluetooth with processing android app

Project on Hackaday.io: https://hackaday.io/project/10286-skateboard-speedometer-by-invented

In this project i will realize to develop a complete product:

-Speedometer(based on Arduino with bluetooth module, hall sensor and LiPo battery) -3D-Printed Housing(this Speedomerter should to work for streetskating, grinding & sliding) -Arduino program for Speedometer -Android App made with Processing

First impression;): https://youtu.be/CC7X-Vp8hto

When the wheel is turning a bar magnet(drilled a hole and put it in the wheel) is passing hall sensor and a revolution can be recognized. That´s the way it works. Sending the data to smartphone via bluetoothHC-05(will change to 4.0 BLE, HM-10). In the app you can read the speed(kmh), distance(m) and wheel revolutions. My app is still missing max speed, average speed.......

In future i would like to add an gyroskope and add and "recognition" for various tricks. Maybe any kind of hight detection for ollies?:-) Many ideas for more...