A few thoughts on this: (1) The City's attitude toward these mobile apps, which facilitate a market for public parking spaces, is that they are creating a "predatory private market for public parking spaces" by "hold[ing] hostage on-street public parking spots for their own private profit." But there's another way of looking at what is happening here. These apps aren't allowing drivers to "rent" public parking spaces--something which they do not own; rather, they are enabling drivers to sell their legal right to occupy the space. Perhaps this is just a semantic difference, but I find it irritating that they liken it to a predatory market for property they don't own.

(2)Regardless, it is clear that apps offering financial rewards for leaving a spot would violate the SF city code prohibition on contracts concerning the use of a parking space. I think these companies could easily avoid this legal snafu by adapting their model to provide other incentives for users to provide updated information about parking spots. Rather than offering to pay users each time they give a parking spot to another user, these apps should offer these users points--or "Parking Karma"--for each trade. Users with high Parking Karma could receive special benefits--like being the first ones to receive updated information on parking spots that become available in their area. They could also be given the option to message with other drivers in the area to discuss when they plan to leave a desired spot (and each successful trade would result in more karma points to both drivers who participate). There are many ways this could be executed, and I hope these apps pivot and adapt rather than shutting down. They provide such an important service by aiming to reduce the frustration associated with public parking and achieve a more efficient distribution of public resources.