When we live in a global village, then maintaining privacy and confidentiality becomes reasonably challenging. Short Message Service (SMS) is the oldest application for exchanging messages between communicating parties in cellular network used by mobile phones. These messages are encrypted over-the-air with A5/1 algorithm and stored as clear text at network operator. Recent developments have shown that this algorithm is not secure any more. Compromising an access to network operator registers gains access to SMS also. Current scenarios of hacks and exploitation demands confidentiality, and encryption is one of the techniques, which is used, in this subsequent project of designing a secure SMS android application. Cryptographic manipulation of the data is performed using AES 128 -bit algorithm to secure the data, which is essential to us and the safe transmission of confidential data over the GSM network. AES (Advanced Encryption Standards) algorithm is the considered impregnable even to super computers brute force attacks. The AES algorithm technique uses very befuddled and sporadic encryption making data impregnable to attackers or hackers. This android app will allow the user to encrypt and decrypt the SMS (Short Message Service) efficiently and just at one click. Subsequent explanation is given afterwards.