Is My iPhone/iPad Backed Up?

First, check if iCloud backup is enabled:

1. Tap Settings:

2. Tap iCloud.

3. Scroll down and tap Storage & Backup.

   If iCloud Backup is switched on, it will also display the last time a backup completed:

   

If iCloud Backup is not enabled:

1. Attach the device to your PC. Let the sync process complete.

2. In iTunes, click on the device in the left-hand pane. The backup status is shown:
   

   Generally, the Latest Backup should be very recent.