A free app for Android, by WordBit Lockscreen Study.

WordBit is a simple and effective language learning tool that is completely free and available on Android smartphones. The main function is to help you learn the most important words and phrases by displaying them on the screen and also to provide additional information such as word origin, irregular verbs, and so on.

This tool is also a good learning aid for those who are in the process of learning a new language and who want to improve their level.

WordBit can be used as follows:

You can check the words you have learned by looking at the sentences that are included in this app. 

You can also learn words and phrases that suit your level.