Where are you getting these numbers from? Do you have stats to back them up? When I worked as an app developer we would only support back 2 or 3 versions, and t

Where are you getting these numbers from? Do you have stats to back them up? When I worked as an app developer we would only support back 2 or 3 versions, and that was 5 years ago. Anecdotally I have not noticed a shift to only supporting more recent OSes.