If you are using Mac, 3 steps:
1. Connect the device to your computer. iPhoto should automatically launch.
2. Click Import All.
3. When the photos finish importing, you will be presented with a dialog asking whether you'd like to delete the original photos from your Camera Roll. Click Delete Photos.
If you are using windows, 5 steps:
1. Connect your pad to computer.
2. Choose Start > Computer. Right-click the logo for your device and click Import pictures and videos.
3. Click the Import Settings link. In the resulting window, you can change the folder to which your Camera Roll's photos will be imported by clicking the Browse button next to the "Import to" field. By default, these will be imported to the My Pictures folder.
4. Enable the option, "Always erase from device after copying". Click "OK"
5. Wait until tranfering completes, Windows Photo Gallery will launch with your photos.
For more detail please refer to
http/support.apple.com/kb/ht4083
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