Timelense - Bring postcards to life using AR (and a sprinkle of magic).
Spacewolff - P2P marketplace for ads. Turn excess space into ad space.
Send Mail Get Mail - A postcard-sending website.
StickerRide - Let your car earn money through advertising
Local Mail by Mailjoy - The easiest way to mail potential customers in an area
Grabb-It - Location-based ads on your Uber's window