vatech systems blogs

Each Android application in general runs under its own unique ID, and it is different from desktop environment where most of the applications run under the logged-in user ID. Android OS creates an isolation boundary around each process to prevent one application from directly accessing another application’s data. From the other side it is possible to have a data sharing between applications. For example, process can query a content provider of another application, or invoke an activity in another application. To protect the user from malicious applications, Android requires applications to request permissions if they need to use a protected feature (such as contact data), features (such as the device’s camera) and by default applications cannot access them. At install time, the APK installer either grants or denies the requested permissions based on the signature of the .apk file and/or feedback from the user. If a permission is not granted, any attempt to execute or access the associated feature will result in a permission failure (access denied).