TL;DR
Aaron Christophel has successfully managed to run Doom on the Xiaomi Mi Band 10, a budget smartwatch known for its impressive battery life. The project involved overcoming significant technical hurdles, as the Mi Band 10's hardware is based on the Bestechnic BES2700iMP system-on-chip, which lacks a public software development kit (SDK). Instead, Christophel had to work with a leaked SDK from a related chip and reverse-engineer the necessary components, including figuring out how to communicate with the device's hardware.