Despite numerous attempts, I had never managed a decent shot of the Moon using an iPhone. When showing people how to do afocal photography, I have leaned how to make just about any compact camera perform nicely, but routinely seen nothing but trouble with cell phone cameras.
Lunar photography is incredibly popular with folks using the telescope, a great activity for a night with a bright moon. Long ago I found that an inexpensive 20-25mm Plössl is a good match for the lens of most compact cameras. On a 1-2m focal length telescope this combination can produce very nice lunar photos. The setup does not work with cell phone cameras. Though people do try, the results have been routinely disappointing.
Working a resort star party recently, I discovered a combination of telescope and eyepieces that works very well. A C11 telescope, an f/6.3 focal reducer, and a 20mm Nagler type 2 eyepiece produced very nice photographs with several different cell phone cameras. The result was a very happy audience and a lot of great lunar photos. As people walked away from the telescope they were rapidly replaced by a crowd holding glowing screens, all wanting to get a nice lunar shot for themselves. I will have to explore other telescope/eyepiece combinations to find another solution that does not involve a $500 eyepiece.