Using the device's display to create a kitchen timer that can be reset by pressing a button.
It may be hard to find documentation for this device, if you need it check it's datasheet found in the docs directory if you follow this link. there is a section that links to various helpful locations including the directory linked with all it's reference manuals and datasheets for the technologies involved.
This project uses the lcd library by github user slmisc. The main pull is the support for dma between the screen and the board, allowing faster refresh rates and other cool stuff.
This project used to use code from Kevin Sangeelee's git repo which helped the project get to a workable state. I would recommend it as a good example project using alot of the Sipeed Longan Nano's features.