Encrypted SMS application on Android with combination of caesar cipher and vigenere algorithm

The use of SMS application is not a new topic this days, But it is un-denied that the SMS method is the classic way to do the messenger activity but still use by the user in communication activity until now. According to research before with Abdur Rahman author ever read, therein explained that the encryption method used is the Caesar cipher with a number of 95 characters. And there are limitations to input only 50 word text message, authors also wish to test security and performance when combining the two methods of encryption. The author tries to combine the Caesar cipher encryption method and Viginere cipher encryption method. The number of characters 94 and there is no limitation on the input text message. So, in this research the author intents to develop the recent research to improve the previous research to make it better. In the end of the chapter of this thesis, the author will give the conclusion of the study that this application was made to improve the security of the encryption of text messages, and prove that the merger of two classical methods of cryptography can be implemented on Android smartphone.