Check the repository with the schematics and firmwares GitHub/elmameto/handy More details and updated info about the project on hackaday/elmameto/handy Building instructions on [not still available ] A couple of months ago I started building an electric longboard and since then I've been using as a controller one of those big gun-shaped radios used for RC cars. Not very good. They are unnecessary big and heavy, the battery lasts too little (and cost too much) and you can't add any custom functions.  There's also the nunchuck way, which is very common among EL builders, but I don't really like the idea to have to keep my hand in a locked position to have consistent speed. Use the lever to set an acceleration? Even worse.  Having a self made bluetooth controller comes handy and has many advantages: It's way smaller, even if handmade. An integrated SMD version would be probably half as big. You can add a bunch of custom functions. Like battery check, lights control, music, autopilot, wormhole and others. I't open source :)