2. Circle of 6

On iTunes: itunes.apple.com

You know a security app for the iPhone is good when the White House has endorsed it! Circle of 6 is an app which sends pre-set messages to a circle of 6 people who you have chosen to in an emergency situation. You can customise the message to contain your location or address, and there is even an option to request that the person calls you as soon as they can. The app was designed with young college students – mainly girls – in mind, but works very well for anyone regardless of age.