It would be very nice indeed to have a range of user-configurable options for what the two buttons will do - maybe this is something that could be looked at in a subsequent version?

The possibilities for widespread use of the proximity sensor across many apps seem tantalising, but it's not great for every app to have to do this individually.

For example, I think a nice idea would be for proximity to toggle between normal and cursor mode in the browser ui.

Maybe if a standard k/b modifier event was put in place (right alt?) as an option here, it would make it easier across the board for apps to take advantage of the possibility (without having to write their own proximity-polling code in each case) so that (for example) the mod to the browser-ui would just take the form of adding behaviour for a standard k/b modifier?