Did You Know? is an Android app that aims to increase your general knowledge by providing you with interesting facts every day. You can choose from over 20 topics, such as history, nature, science, music, and human body, and decide when and how many facts you want to learn. The app will then randomly display a fact on your lock screen at times you have specified.

If you are busy and can't read the fact at the moment, you can simply click the "Show Later" button and read it later. If you have time to read, click the "Got It" button to dismiss it. You can also add your favorite facts to a list and repeat them anytime you want.

The app also allows you to learn fun facts anytime you want, not only on your lock screen. Did You Know? is free, offline, and has a database of over 20 topics and 1900+ facts, which the developers continuously update.