Apple’s iCloud is an awesome free storage service that lets you store music, photos, apps, calendars, documents, and more on the Cloud. Also it wirelessly pushes them to all your iOS devices automatically.
The free iCloud service offers everyone with 5 GB space to starts with and once you reach the cap you can subscribe to a premium account with few dollars of fee. If you would like to monitor iCloud usage details here steps to be followed on an iOS device
1. Tap on Settings app
2. Choose iCloud from the list of available options
3. From the list of iCloud settings tap on Storage & Backup option
4. Under Storage section you will find the details of iCloud usage – Total Storage and Available Storage