Have you ever wondered if people are spying on you? Not to be paranoid or anything, but we all leave our phones unattended sometimes. It's not hard for a friend—or foe—to take a quick look at your text messages. But don't fret.
Catchr ($2) does one thing, and it does it pretty well. Once you install the app and quit all of the apps you have running, Catchr will record all of the most basic activity on your phone, namely which apps are opened and closed. (It doesn't work on the Mail app due to App Store rules.) It will also tell you if your phone has been moved and show you where on a map, though it's not very precise as you can see in the map above.
So if you think someone's tampered with your phone, you can just check Catchr to see what they did. It's helpful if you can remember the last thing you did on your phone. Also be aware that it doesn't work so well in groups, since you can't know exactly who did the snooping. For that, you'll need to catch a friend in a one-on-one situation.
What Catchr can't do is protect you. For that just use a passcode. Catchr isn't about protecting your phone, though. It's about counter-surveillance. Just make sure you're ready to find out who your real friends are. [Cult of Mac]