The Nokia N81 is a smartphone announced by Nokia on 29 August 2007 and released the next month.
The N81 was marketed as a mobile gaming device, similar like the 2003 N-Gage. It was the first device that came preloaded with the N-Gage 2.0 gaming service in 2008 (albeit in public beta), and it came with 2 dedicated gaming keys that can be used for N-Gage games and other applications. The four-way navigation key, the silver-coloured slightly rounded square key below the display, also contains a capacitive sensor. Some firmware revisions allowed the user to scroll through options by 'stroking' the key in a similar manner to the click-wheel on some models of iPod. During the launch of N-Gage, the N81 was specifically chosen by Nokia in advertisements. The N81 is notable for being the only N-Gage 2.0 device with special gaming keys.
The Nokia N81 suffered from lower sound output due to the release of the new firmware version. According to Nokia, they must follow an international standard wherein a device's initial or default volume must be set to low to avoid any damage to its users.