A free app for Android, by SEStudio.

Do you want to learn more about the English language so you can use it anytime and anywhere? Then this English Grammar Handbook will surely help you. This app is very easy to use and understand. You can learn English easily using this app. There will be also a practice section and some video lessons to learn more about the English language. 

After you read and practice some of the grammar you can take a quiz to test your knowledge of what you have learned from each lesson. There is the part that will also enhance your vocabulary in order for you to construct your own sentence. Download and install this free app and continue to learn more about the language