Echo lets you go back in time and record something after it has already happened. Record harassment and bullying (even when you didn't anticipated them). Save pieces of information (phone numbers / passwords / instructions). Record cute/funny moments. Prove that someone said (or didn't said) something. Enjoy! Bugs.
Marek Rogalski is the creator of the app that can be found in the Tools category. Over 10K users set up Echo and the most recent update was released on Oct 28, 2014. Google Play displays that this application is rated 3.9 by its users.