InfoPad is very useful app that can be used to manage all kind of information as a personal database on your iPhone. Especially it's very dynamic, you can define your own data structure. and it's also very secured.
Youtube Video: http://www.youtube.com/watch?v=00zJLKK6htI
InfoPad full: https://itunes.apple.com/app/infopad-ultimate-personal/id629215951?ls=1&mt=8
InfoPad Lite for free:https://itunes.apple.com/us/app/infopad-lite-ultimate-personal/id633241358?mt=8
Youtube Video: http://www.youtube.com/watch?v=00zJLKK6htI
InfoPad full: https://itunes.apple.com/app/infopad-ultimate-personal/id629215951?ls=1&mt=8
InfoPad Lite for free:https://itunes.apple.com/us/app/infopad-lite-ultimate-personal/id633241358?mt=8