Just made the first prototype of my backpack patch/pin that uses epaper. You can open an app on your phone, select the device, select an image and the app will process it and send it through Bluetooth to the device. I also plan to support different display types so for eg. you can have the music you are currently listening to along with a visualizer on your backpack. I think about starting a Kickstarter and a shop, but I don't know whether people are interested in something like this. Would you guys be interested?