Highly volatile requirements of mobile applications require adaptive software development methods. Several attempts to address challenges in mobile software engineering have found agile methodology to be appropriate for mobile application development. This project report provides a detailed analysis on various challenges involved in mobile software development which are addressed using Agile-SCRUM methodologies. An efficient mobile software development concept derived from Agile-Scrum methodology is designed in this project. A light-weight Android application for secure and incremental backup has been developed using the proposed methodology. An in-depth illustration of the practical experience in developing the application has been discussed. Unlike other prominent languages like Java, the use of Python for Android platform has emerged recently. Hence developing the secure-backup application in Python was a challenge, which has been dealt in this report. We believe our proposed methodology has a potential to help developers deliver improved quality of mobile applications in short time.