Here's how to check your cellular data usage on an iPhone, and find specific readings for and manage each app's data.

Most mobile carriers have a phone line for data usage checks. You can also see how much data is left in your online account or the company's app Data can cost you big bucks if you're not paying ...

Spotify's data usage depends on what you're streaming and the quality you choose. Fortunately there are a couple of easy ways ...

FaceTime calls do use data, and you can check how much through the Settings app on your iPhone or iPad.