Android app

We need an application that is a: 1- E-reader for pdf's 2-Is an android app 3- Can make notes in the pdf and save the notes 4-Can send the pdf with the notes to an email This application is for a school, they want to get rid of books and they are encouraging students to use tablets. The books are already in pdf form, and there are books that are full of exercises. Whenever a student sees an exercise they should write in the page and should be able to send them to their teacher via email and save the exercise that they wrote.