I’ve released version 3.0 of Priorities App a few weeks ago and added a new todo feature with this update to the app. This is what users and customers see when they work with Priorities App and use it in their daily business. But that’s only the foreground. Behind the scenes, Priorities App has completely changed and was completely refactored with this new version 3.0. In concrete, the complete code base has changed. I’ve rewritten the app completely in Swift and migrated all Objective-C classes to Apples new programming language. And in this article I want to give you an insight of the experiences I ‘ve made while I migrated a complete iOS project.