Using Uniform Type Identifiers (UTIs)

Recently I had to determine what type a given file was for my macOS app Media Explorer. For example, is it an image? a video? or a document? An easy way to do this is by using Uniform Type Identifiers.

A UTI is an identifier that a given extension can fall under to help identify it’s class or type of item. There are broad UTIs such as public.image, and more precise UTIs such as

We can use these to group together files of a certain type or to identify a certain type of file we are interested in.


… but what if you haven’t had time and let the technical debt build up?

As a developer, there is no doubt that you’ve heard the terms Test Driven Development (TDD), Behaviour Driven Development (BDD), Technical Debt and the many others out there. You can read books, posts, watch videos and learn from tutorials about it, but there has probably been a time when you’ve entered a project with little to no automated tests.

There may be a thousand reasons why your current test suite may be lacking, it could even be that you inherited the project in this state. …

Scan and open URLs directly!

There are many reasons for and against having an in-app tutorial. Some say that your application should be designed such that the user either instincitvely knows how to use your app’s features, or that the user should be introduced to features as they use the app (a la Slack). However, sometimes it’s nice to have a simple tutorial from the beginning to explain the core functionality quickly.

I believe that if you are going with the simple tutorial option, then you should use as few words as possible, maybe even none apart from “Skip Tutorial”. My latest app (Urly, iOS)…

Francis Hart

iOS & macOS Developer. Tech enthusiast. 🚀 Software Engineer at @MobileCaddyOrg. Creator of

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