What was the first Nintendo Switch model to use an OLED display?

The first Nintendo Switch model to use an OLED display was the Nintendo Switch OLED Model.

Nintendo announced this revision in July 2021 and released it on October 8, 2021. Its 7-inch OLED screen offers stronger contrast and deeper blacks than the 6.2-inch LCD screen in the original Switch, while keeping the same 1280-by-720 handheld resolution.

The OLED Model also introduced a wide adjustable stand, a dock with a wired LAN port, 64 gigabytes of internal storage, and enhanced audio in handheld and tabletop modes. It remained compatible with the existing Switch game library and Joy-Con controllers.

It is not a higher-performance successor in the way a new generation console would be. The processor and general game compatibility remained aligned with the standard Switch family, making the model primarily a display and hardware-design revision.