Windows Phone 7 users are complaining over what they call "phantom data usage." The nascent smartphone platform is, according to some accounts, using as much as multiple megabytes per hour of cellular data, and that's even when connected to wi-fi.
Indeed, you read that correctly; even when connected to wi-fi, Windows Phone 7 seems to be defaulting to cellular connectivity when there's a wi-fi network that the users's phone is connected to. In one report, a user stated that his bill showed:
