Looks like a small but massively significant update has gone out for the Surface app. Version 10.0.342 is now live in the store and it is going to make a lot of folks happy.

The Surface app, which comes pre-installed on all new Surfaces, finally now lets you customize the rear 3-way button on the new Surface pen for Surface Book and Surface Pro 4 (it also works with Surface 3 and Pro 3).