holoride on its own uses up at most a few MBs per hour.
The holoride App runs on your VR headset and requires an internet connection. If you provide this internet connection via your smartphone you might be worried about the amount of mobile data it uses up.
Since the internet connection is generally only used for localization purposes it will not use up too much of your mobile data volume. Depending on the distance traveled while playing we do not expect the used bandwidth to exceed a few MBs per hour.