File Locker: For iOS - Free
Apple devices already provide a decent level of password protection, although there's no such thing as being too careful. File Locker brings an additional layer of support for sensitive data -- including text, images or other files. It locks down files on an iPhone into a separate folder on the device. The app itself requires entry of a security code (that you select), and provides protection to as many as five files.
Files can be sent directly from an iPhone's camera, from a network server, from a URL or from text that you enter directly into the app.