Sonic Dash is an endless runner, similar to Temple Run (2011) and Rayman Jungle Run (2012). The player directs Sonic or another character through levels, collecting rings and avoiding obstacles and enemies. Unlike other games in the series, Sonic automatically moves forward at all times, similar to Sonic and the Secret Rings. Players are able to share and compete for position on leaderboards.

The game features 3D graphics, including a level set in an environment based on the Seaside Hill level of Sonic Heroes. Rings can be collected throughout the levels or purchased via microtransactions, along with red star rings. Accumulated rings and red star rings can be used to purchase power-ups, upgrades, or unlock additional playable characters. The game also features a mission system, giving players an objective to target as they play the game. The game features several playable characters from the Sonic universe.

Characters are unlocked by purchasing them with red star rings or real-world currency. After the game's release, further updates added additional characters and new features. On October 31, 2013, an update was released that included a boss battle against Zazz, a member of the Deadly Six from Sonic Lost World. A similar boss battle against Doctor Eggman was added in a later update. Several characters from other non-Sega franchises have been added to the game as part of temporary cross-promotional events, available to unlock only during a limited time period.

These include the Angry Birds characters Red, Chuck and Bomb during June 2015; the Sanrio characters Hello Kitty, My Melody, Chococat and Badtz-Maru during December 2016; and Pac-Man and Ms. Pac-Man in February 2018. The Android version of the game also features an exclusive character in the form of the Android robot. Content themed around the 2020 Sonic the Hedgehog film has been added, as well as a "Zone Builder" feature.