I think that there should be a Tip Jar option when you complete your journey, That way when you arrive at your destination, thinking that Waze really helped you out, you could drop a couple of pounds/bucks/euros into the Tip Jar. Maybe it would need to take the form of an in-app purchase for which you'd receive a badge in order to justify the purchase.. I don't mind the ads but they aren't relevant to me and on a number of occasions I'd have been more than happy to say thank you by sending a few quid to Waze.