Go Map!! v3.0 was released today for iOS, and while superficially not much looks different, there are some big changes under the hood: All 38,000 lines of code are now written in Swift after a laborious conversion from it’s original Objective-C implementation. This make the code faster, easier to understand, easier to debug, and brings it in line with Apple’s direction for modern apps. It also greatly simplified a lot of refactoring to improve general readability of the code base. If you’re a developer this is a great time to get involved with the code.

Background

My involvement with OSM started in March 2012 and I wanted to be out surveying and mapping on my iPhone. I had downloaded the few iOS apps that existed at the time (remember iLOE and Pushpin?) and found them too limited. Although I had a strong Windows/C++ programming background I was new to iOS, Objective-C, OSM, and GIS. Nevertheless I began work on the first version of Go Map!! writing in Objective-C and learning about the OSM API along the way. (Apple did not introduce the Swift programming language until several years later, and it took an additional several years to become stable.)

I wasn’t really sure whether a new mobile editor was something of interest to the OSM community, but in October 2012 I drove down to Portland, OR for my first SOTM US, where RichardF (author of Potlatch, the OSM web editor at the time) delivered a talk titled (IIRC) “Let a thousand editors bloom” where he suggested that OSM should have a wide variety of editing tools, and the more the better. I’d been working on the app for only a couple months and his talk inspired me to continue.

Soon after that I began attending the OpenStreetMap Seattle meetup that Steve Coast was organizing at the time. While he was clear that he would never use a mobile editor himself he still encouraged my efforts and provided feedback on the user interface and other aspects of design. He especially disliked my terrible taste in app names, which went through several iterations before arriving at what it is today.

Go Map!! v1.0 was released on the iOS App Store on Jan 24, 2013. The range of features has increased on a slow and steady pace ever since, but due to the inertia of the code originating as Objective-C most improvements were added in the same language for consistency. Going forward all work will use Swift.

Bonus fun fact: Initially I wrote the app for Mac, then migrated it to iPhone. Although the original Mac app is gone you can still build and run Go Map!! on your desktop using Xcode and Mac Catalyst.

Thanks to everyone for your support, suggestions and contributions along the way.