Just Dance 2015 is the sixth main game in the dancing series where players perform dance routines, mimicking the moves of on-screen performers, to earn points. The controls are different for each platform. For Wii and Wii U movement is tracked through the Wii Remote, Xbox 360 and Xbox One require the Kinect peripheral, and PS3 and PS4 use the Move controllers along with the PlayStation Eye and PS Camera respectively. You can also download an app to an iOS or Android phone to use it as a controller. The app connects through the local Wi-Fi network and detects the console for the phones to register, based on the technology used in the game Just Dance Now. That way platform-specific peripherals are no longer required.

The tracklist varies slightly per region, some of the tracks are offered as DLC and there are a number of cover songs. Artists for this edition include Ariana Grande, Avicii, Calvin Harris, Katy Perry, Lady Gaga, Miley Cyrus, Nicki Minaj, One Direction, Pharrell Williams, Rihanna, Stromae etc. As with previous versions songs are divided into different game modes such as Dance Crew, Solo, Duet and new for this version Trio, carried over from Just Dance Kids 2014. For some of the songs alternative routines are offered, along with sweat routines, sweat mashups, non-stop shuffle (absent in the previous game) and extreme versions. Next to the main game modes Dance Mashup returns from Just Dance 3 with new versions of songs based on a specific theme. Just Dance VIP is a new game mode where celebrities record themselves dancing to a song and make it available to as a playable routine. Autodance returns for all platforms except the original Wii where the game records parts of the player's performance and matches the music against it in a short clip that can be shared. The On-Stage mode of Just Dance 2014 with lead and backup dancers does not return.

Community Remix is an entirely new mode. Players can record themselves dancing a custom routine and share it with the community to vote. The development team then turns the highest rated ones into a playable routine for all players. Other people can be challenged used the Challenge mode to beat the score of other players as a ghost version, not as real-time multiplayer which is available in the World Dance Floor mode. The game's social network is called Just Dance Wall. It is possible to sing along in the Karaoke mode. Returning is the Wii U and Xbox exclusive Party Master mode where one player acts as a game master to interfere with the routines of the dancers. For Wii U this is done using the GamePad and for Xbox it requires Smartglass.