This article covers how to ensure you're not using more mobile data than you intend to, with suggestions of things to check on and monitor.
Auto backup or file transfers: If you use a file transfer app or service such as iCloud, OneDrive, Dropbox or Google Drive, you need to make the following changes to save data:
- Change settings to use only Wi-Fi for document uploads or downloads
- Change the frequency of backups from automatic to manual
- Choose which content you want to back up instead of backing up all of it
About turning off automatic backups to iCloud .
App updates: If your apps are set to auto-update, they will begin updating using your mobile data. To prevent this, set your apps to update automatically only when you're connected to a Wi-Fi network. You can also set your apps to download updates manually. This way you can be sure your apps don't accidentally use your mobile data for updates.
Block ads: Pop-up advertisements on websites and even within certain free apps use your mobile data to play their content. You should block these ads using an ad-blocker or close them before they start playing to minimise the loss of data.