This is one of the things I have been waiting for. Thank you, Park Tucson!
Park Tucson is pleased to announce the installation of the first 21 new smart parking meters that will provide improved customer service to our on-street parking guests. The new meters are solar-powered and accept credit, debit, and smart cards in addition to coins, and will soon be accessible for payment through a smart-phone mobile app.
You can get more information here.