Give your simulator superpowers

RocketSim: An Essential Developer Tool
as recommended by Apple

Issue 40
Sep 14, 2025

It has been a week full of Apple-related news. iOS 14.3 got released, a new Xcode update arrived, and privacy labels are the new way to fill the screen.

It's also been a week in which I turned 30 and had a full week of experiencing the new MacBook Pro M1. The results still blow me away. The Collect app I'm working on every day had the following results:

- Clean build: 53s (3.84x faster)
- Incremental build w/o changes: 5s (3.1x faster) 

These results line up with reports from others in the community. It's the difference between staying in your flow or jumping out on Twitter to read some tweets. The only downside so far: I only have two thunderbolt ports, and a hub didn't help me forward to support both an external screen and adapter.

It's not a show-stopper, though! If you're able to get it, I would definitely recommend doing so. Xcode is just so much faster, which is a game-changer, in my opinion.

Enjoy this week's newsletter!

THIS WEEK'S BLOG POST
The Result enum type in Swift is often used since it's been available in Swift 5. However, methods like map, flatMap, and flatMapError, which are available by default, are less often used. My colleagues and I didn't use them often too which is the reason I dived deeper in its usage.

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TWEET OF THE WEEK

I need to get myself a friend like this too!

CURATED FROM THE COMMUNITY

CODE
A great project by my colleague Boris-Em which helps you do anything with colors. Find dominant colors, difference between, color palettes or the average color. Make sure to check it out if you’re working with colors in your project.
Async/await is not yet available officially but you can start playing around with it today if you want to. Eneko explains to us how this works. On that same note; the review of SE-0296: async/await has started!
An amazing milestone for John Sundell, wrapping up the weekly article series with article number 200! It's definitely not the end of Swift by Sundell as he promised but he will step away from the structured weekly flow. Congrats on this milestone, John! (Let's see if he reads this 😉 )

META

Ash Furrow shares his knowledge on knowledge sharing to improve knowledge in a knowledgeable team. An interesting read if you’re working in a team!

VIDEO
Vincent explains to us how we can use "zip" in Swift to combine two arrays. This can be useful in some cases so it's great to be aware of this method!

MARKETING
Niels Mouthaan takes us through his process of improving the App Store performance of his app Daily Time Tracking. The best part is that he shows the before and after results in a graph, making it easy to see his results. ASO is from great value if you want to improve your app's App Store performance.

NEWS
iOS 14.3 dropped this week with Apple Fitness+ and other updates. It also brings updates to Shortcuts for which Matthew Cassinelli does a great job explaining.
Announced earlier at WWDC, App Clip Codes are now finally available. You can use the new App Clip Code Generator to create yours.
Although you’ve probably already noticed you need to fill in the privacy details for your app before a release, you might not have noticed this change in the App Store. Your labels are now live, so make sure to check them out and verify.
Don’t forget to apply to the App Store small business program if you didn’t do so yet! You only have till the 18th of December.

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