Sprayway is fine for the outside but if you read the warnings its not safe for all tint so be careful if you have after market tint.There are glass waxes that are appropriate for cars that will do the same, I think. They get rid of the water spots and are more easily controlled than a spray liquid for kitchen and bath room cleaning.
Sprayway for the win, though. Even better than brand name window cleaners like Windex.