@Dae-0, I agree. And I don't think that it will be a problem.
@Corjan-Meijerink Users of the navigation part of the app, find it very logical to use that button to start the latest driven route again. People who use different means of navigation, will not start any routes for navigation in the app, and the last edited route is openen by that same button (like it is now). When I access the planner to edit or create a new route (be it the mobile app planner or the online planner), I am perfectly fine with it when that route gets opened by that same button. So, I would say one button is enough, and needs to be redefined as "last edited OR driven route" (whichever comes last).