If you're looking for a simple app with password protection for photos and videos, check out Photo Vault. Simply type in your PIN and import as many photos/videos as you'd like! After importing photos you can organize them in folders, upload them to a computer via WiFi, and delete them from your regular library so that no one else can see them.

If someone gets into your iPhone (if you don’t have a passcode, that’s easy to do) , it would be very easy to take a look at all the photos on you iPhone. With Photo Vault, privacy is no longer an issue since the app protect your photos with a password; something that the iPhone photo app doesn't do. You can even take it a step further and password protect individual albums within the app. To do so, just create an album with password protection!

In total, this app includes great UI, password reset , touch and fullscreen, zooming feature, and WiFi photo transfers. Upon closing and re-opening the app, you will be required to enter your password every time. Enjoy!