Owners of Inventist's Solowheel Xtreme can use this free app to display the battery charge and speed on their Android or Wear device. (Xtremes only. Solowheel Classics do not support Bluetooth.)
With an Android Wear smart watch you can leave your Android phone in a pocket or backpack and simply glance at your wrist while gliding to see the battery charge and speed.
The battery gauge is based on the voltage reading transmitted by the Xtreme. The fully charged voltage is displayed as 100%. Empty on the gauge is when the Xtreme is going to start wobbling to force you to get off. Batteries do not drain at a steady rate. In normal use, the Xtreme's voltage drops off quickly after being fully charged and then stabilizes during the ride. Please don't assume the battery charge percentage translates directly into how far you can ride.
When descending downhill or slowing down quickly, the Xtreme uses regenerative braking. The battery gauge will temporarily increase on downhills as the Xtreme uses your kinetic energy to charge the battery. The gauge will provide a more accurate battery reading once you're back on level (or uphill) terrain and the battery charging stops.
For Android Wear support, the custom watch face is installed automatically. Be sure to first install the Google "Android Wear" application from the Google Play store, and then pair your watch and phone with this app. If your watch is having trouble connecting with the Xtreme app on your phone, first verify that Google's Android Wear app indicates the watch is connected.
The Solowheel Xtreme stops announcing itself for Bluetooth pairing once connected to the phone. If the app completely loses the connection, you may need to power cycle your Xtreme so the app can find it again and reconnect.
If your Xtreme has non-standard Soloware firmware, it may not work with this application.
Currently the only data received over Bluetooth LE from the Xtreme is battery voltage, speed, and direction. (No distance.) You probably already have several amazing GPS navigation apps on your phone that can provide distance. The Xtreme's blue LED battery meter doesn't provide much warning before your ride ends unexpectedly short of your destination. The most important feature we wanted to get out quickly is a better battery meter. Please remember that this app is limited by the capabilities the Soloware firmware provides and upgrading the firmware in Xtremes with future improvements will take time. Inventist has been very helpful and supportive on this project. I'm sure they will welcome and read your suggestions for improvements with great interest here.
I'm a Solowheel fan, mobile developer, and gadget nerd. I want this app for my own use and volunteered my time to build it. If you enjoy your Xtreme as much as I do, how about rolling up your sleeves and helping to make this app better? The source code is up on GitHub. Can you think of a more fun open source project to contribute to?