"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 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's about counter-surveillance. Just make sure you're ready to find out who your real friends are."

We have received a lot of interest.

There are few examples

"Catchr records which apps you open and close and whether or not your phone's been moved. So, if you leave your phone unattended on a table and your friend decides to poke into your text messages, you'll see that they opened it and how long they had the app open for."

"Catchr is a fun application — and likely one of an increasing wave of privacy-oriented apps and other services we’re likely to see in the near future."

"Have you ever left your iPhone on a countertop or coffee table and wondered if a curious friend or family member did any snooping? Catchr is an app designed to answer that question by tracking all the app activity that happens on your device."

"[…] like Touch ID, Catchr is all about privacy. Touted as a "privacy guardian" that helps you keep your private stuff private, Catchr is a deceptively simple app that lets you surreptitiously find out if someone else has been using your iPhone while you’re away."