An interesting challenge of this build was developing a way that users can interact with a device in an urban environment but also give them little opportunity to tamper with or destroy the device.
One of my first thoughts was to have users interact with the device using a laser pointer. This would allow the device to be placed far enough out of reach that users could not easily tamper with it but would have no issues targeting it with a laser pointer. I ultimately gave up on this approach because there is a signifant amount of low flying air traffic at the park where I had considered installing the device. That and the other hazards of laser pointers that make them less appropriate for children.
The final solution I arrived at was enabling users to interact with the device by tapping on a metal pole. I was already planning on mounting it to a metal pole using a magnetic mount so this made a lot of sense. Just like the laser pointer solution it can be placed out of reach. The additional benefit is that a special tool is not required to interact with the device. Users could just tap the pole with a stick or maybe the side of their phone.