Nintendo’s Super Mario Run for iOS is a single-player game. There are some multiplayer aspects in the game, such as being able to compare your run against that of your friends, as well as adding friends to your list, but for the most part you don’t really need to interact with anyone else.

This is why many gamers were surprised that the game required an always-on connection, although Nintendo said that this was meant to help combat piracy. However it seems to have a rather unfortunate side-effect, and that is it seems to be consuming a ton of data. According to users, there are some complaints of the app eating up too much data.
This means that unless you’re on a WiFi connection, you could easily blow through a chunk of your data in no time. AppleInsider notes that it can consume as much as 75MB per hour if you’re playing non-stop, and some users are claiming that they’re seeing the game consume up to 150MB due to repeated downloads.

AppleInsider was also told by some of their sources, “The game is chatty. Nintendo’s doing a lot of fat-packet data shuffling back-and-forth to its own back-end, and if a packet fails, it’ll keep trying for a bit until it gives up and errors out. This is all data use.” If you’re on unlimited data then you’ve nothing to worry about, but if not you’ll want to keep a close eye on the game. Hopefully Nintendo will be able to address this in future updates.