Parking in a big city is one of those tasks that seem to often inspire annoyance. Just as well, plenty of apps have stepped in to improve the experience.

But San Francisco’s City Attorney sent a cease and desist letter to one such app maker this week.

MonkeyParking tries to match people looking for parking spots and people willing to leave them, and does so for a price. The app allows people to inform others that they are leaving a spot, thus opening it up for bids. The evacuator can be paid as much as $10 by the seeker, a prospect the city is not enthused with.  

San Fransico says the app involves the buying and selling of city property. The app maker counters that it it simply selling information. 

Mike Billings, who covers tech and venture capital for the Wall Street Journal, notes that the city itself has experimented with creating parking apps, thus adding an element of public-private competition to the story. 

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