You have accidentally deleted an important photo or video from your Android device and want to recover it. First of all you should first verify where your phone store photos or videos (Camera > Settings). If they are stored on the memory (SD) card of your device, then it's better to use software like Recuva to recover your deleted items. But if the deleted photos or videos where stored on the internal memory of your device, then the only hope is to use the DiskDiggerapp.
Warning: This procedure only works on rooted Android device. While there are several online tutorials explaining how to root your Android smartphone or tablet, they are to be performed at your own risk.
When you delete a file, the system only deletes the information relating to its location on the device memory. A deleted file can be recovered as long as the memory space it occupies has not been overwritten by new data. Avoid installing new apps, take new pictures or copy data to your phone until the recovery procedure has been completed.