I've been vibe coding SwiftUI menu bar apps for my new Mac, turns out Claude Opus 4.6 and GPT-5.4 are both competent at Swift programming, no need to even open Xcode! https://simonwillison.net/2026/Mar/27/vibe-coding-swiftui/
Vibe coding SwiftUI apps is a lot of fun

I have a new laptop—a 128GB M5 MacBook Pro, which early impressions show to be very capable for running good local LLMs. I got frustrated with Activity Monitor and decided …

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@simon I have been writing iPhone apps this way too. I have 5 now, but haven't paid the Apple tax, so I can run them on real hardware.

My first two are in Flutter, then I decided to have Claude port them to Swift and it's been nice.

I have a TV viewer app so I can use a FireTV, both audio and video, on my Mac and it nailed it.

@webology @simon I've had a need for an iOS app for a while but never had time to learn. Claude knocked it out in a weekend and I'm about to submit to the App Store. Gotta try some menu bar apps now!

@jcarbaugh @simon I'd love to know how that goes. I have two iPhone apps that I want for PyCon US, but I thought I should probably set up a new LLC first before paying the Apple tax.

I was really happy with how my PNP app came out. I don't have my hdmi+usb input here, but it makes it possible to frame an AV source, resize, and float it over other windows.

@webology very cool! How many iterations did it take to work with audio and video inputs? I've got an AirPlay/Raspberry Pi project on my todo list.

I debated over an LLC for the App Store but am keeping it US only to hold off until I'm ready to set one up for EU trader registration.

@jcarbaugh My MVP was a one-shot. I started it then walked with Frank to get coffee and when I got back it was built and running. I put 45 minutes into over that day to get everything look how I wanted.

This was a month ago and I was using Claude 4.5 but used Codex to fix some crashes trying get resizing the window to respect our input video's aspect ratio.

I'm not doing AirPlay though.

@jcarbaugh CC has been amazing for hardware though. I connected an old Kindle Fire to an RPi4 and asked CC to connect to it and use a web browser to grab a screenshot and it didn't miss a beat with ADB even over a weird setup where it has ssh'ing from my mac.

I have had similiar luck with Home Assistant and even some random ESP gear with micro python.

I don't think people realize how good this is.

@webology @simon does this mean, if I write my own app and want to put it on my own phone I have to pay apple?