I’m developing an app for iOS where I have one image showing the degrees (from 0 to 180) and a second image representing a red arrow.
I want the arrow to simply rotate according to the input the user enters in a numeric field from 0 to 180.
At the moment the arrow rotates about its center (corresponding to the center of the arrow image), however I’d like the arrow to rotate from the bottom. In short, my question is: how can I rotate an image about an arbitrary point using Xcode and iOS SDK?
Here is an image I prepared to show visually the issue I’m having:

I suggest looking into
UIView‘stransformdocumentation and theanchorPointproperty: