I'm working on an iOS app where the user can input 2 UTM locations, but the user is inputting 2 UTM locations with different UTM zones and I need to project one of them into another zone.
I tried to use libraries to do that, such as PROJ4Swift (it user PROJ library) but is not working anymore and is outdated.
I tried to use ArcGIS for swift, but I wasn't be able to do that using the SDK
Can someone help me with the algorithm to do the math? Or suggest a library that works?