"The Android Java style guide recommends its use" There is no such thing as an Android Java style guide that provides any guidance on how you should write Java code. "The extra information helps in code review" The 'm' or 's' prefix on name indicates a private/package instance field or private/package static field, respectively, where this would otherwise not be known in code review. So when you see the usage of a field, which piece of information is more important for the review: the visibility of that field or the type of that field?