By the end of this project, you will be able to implement the following validation techniques: Presence checks, length checks, type checks, email validation, credit card validation, and date validation. This will prevent any users of your app from inputting invalid data that may break your app. In This project, we will use Java with the Android Studio IDE. This project is for anyone with at least basic experience with Java and Android Studio with an interest in mobile app development or validation. Anyone familiar with methods, variables, if statements, loops, and classes can follow along. This project will put you on the right track to being a better mobile app developer by helping you avoid some common mistakes and demonstrate more efficient practices. Validation is common on many Computer Science syllabuses and knowing about validation will help the development of more polished applications.