So you decided to stick to the Raspberry Pi architecture and have completely eschewed the Orange Pi? Good for you. In honor of your decision I offer a new $60 Raspberry Pi touchscreen that can turn your single board computer into a fun-sized multi-touch tablet.
The officially licensed product connects to the RaspPi’s DSI and DPI connectors to avoid using the precious HDMI connector and can be powered from the board itself, allowing the entire system to be self-contained. You can even run dual displays via Raspberry Pi and the system can accept touch input. Once you’ve got it all connecting you can download a Python package called Kivy to begin programming for the touchscreen. Because you’re using a Raspberry Pi you can add other input devices as well and even make a touchscreen home automation system with your Pi and some relays. In short, it’s a great little package.