Nintendo DSi system software

The Nintendo DSi system software is a discontinued set of updatable firmware versions and operating system for the Nintendo DSi handheld video game console and its XL variant. Released alongside the console in Japan on November 1, 2008, and later worldwide in April 2009, the system software represented Nintendo's first implementation of downloadable content and comprehensive online services on a handheld platform.

Source: Wikipedia — Nintendo DSi system software (CC BY-SA 4.0)