A free program for Android, by SMSROBOT LTD.

Vault – Hide PhotosApp Lock is an easy-to-use photo and video vault that can secretly hide pictures and videos on your smartphone. The app uses a secret PIN code and a pattern to lock and unlock the vault, and you can also use a fake crash dialog to make it look like your app has crashed. The app can also create a backup of your data in the cloud and restore it on a new device.

Vault – Hide PhotosApp Lock is designed to be as easy to use as possible, and the interface is simple and intuitive. You can add, remove, and rename photos and videos in the vault and import pictures and videos from your device.