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Icon Composer: Transforming an AI-generated icon

Icon Composer is Apple's recommended tool for generating app icons for all the latest OS versions. It's bundled with Xcode ...
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  •  4 min read / Workflow

SwiftLee in 2025: A full year as an indie developer

The year 2025 is coming to an end and did it go fast! It feels like the way we develop ...
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From App Idea to 10K MRR – YouTube Series

You have an app idea, but how do you get it to 10K Monthly Recurring Revenue (MRR)? I have quite ...
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YouTube Videos

Agent Skills solve one of the biggest problems with AI coding tools: consistency. In this video, I show how I use Agent Skills in Cursor to refactor a real Swift app using a Swift Concurrency skill — step by step. I’ve been using tools like Codex, Cursor, and Claude Code for a while, but I kept running into the same issue: best practices and skills lived in project-specific AGENTS files, and keeping them in sync across projects was painful. That’s where Agent Skills come in. In this video, you’ll learn: - What Agent Skills actually are (and how they differ from AGENTS files) - How to install Agent Skills once and keep them up to date - How Cursor discovers and applies Agent Skills automatically - How I use a Swift Concurrency Agent Skill to plan and refactor a real app - Why Agent Skills improve correctness, consistency, and trust when refactoring with AI This isn’t a toy example — it’s a real app, real technical debt, and a refactor that needs to be done carefully. If you’re a Swift developer using Cursor (or considering Agent Skills), this video shows how experienced developers can work with AI without giving up engineering judgment. 👍 If this video helps, consider liking it and subscribing for more deep dives into Swift, AI-assisted development, and building real apps. Subscribe to my channel here: https://www.youtube.com/@avanderlee?sub_confirmation=1 CHAPTERS 0:00 – The problem with AGENTS files across projects 0:29 – What Agent Skills are (open format overview) 1:50 – Agent Skills vs project-specific AGENTS files 3:18 – How Agent Skills are discovered and applied 4:05 – Agent Skills adoption in Cursor and other tools 4:46 – Introducing the Swift Concurrency Agent Skill 6:03 – Skill structure: entry points and references 7:45 – Why skills should be created by domain experts 8:53 – The real app we’ll refactor (context & constraints) 9:37 – Installing an Agent Skill with Open Skills 10:31 – What changes in the AGENTS file 11:12 – Planning a Swift Concurrency refactor with Cursor 13:47 – Interpreting refactor insights and priorities 14:54 – Final thoughts and next steps 🔗 References & Links Swift Concurrency Course https://www.swiftconcurrencycourse.com Swift Concurrency Agent Skill (GitHub) https://github.com/AvdLee/Swift-Concurrency-Agent-Skill Agent Skills (open format) https://agentskills.io From App Idea to 10K MRR – YouTube Playlist https://youtube.com/playlist?list=PLg4qABgFp_nRYMtGFdXz8sUeXb2IDxdPL&si=pKZosWay0bbOWjD6 ⸻ 👋 About Me I’m Antoine van der Lee — Swift developer, indie founder, and educator. I create in-depth content about Swift, Swift Concurrency, AI-assisted development, and building profitable apps as an indie developer. I run: - SwiftLee – articles read by Swift developers worldwide - SwiftLee Weekly – a weekly newsletter for Swift developers - RocketSim – a Mac developer tool app to speed up iOS development - Advanced Swift courses, including Swift Concurrency Subscribe for practical, senior-level Swift content focused on real-world apps and long-term maintainability. #AgentSkills #CursorAI #iosdevelopment #SwiftConcurrency #AIForDevelopers
Refactoring a Real App with Agent Skills in Cursor
YouTube Video VVViSXV4QTZNLVE5QXRLZ1FKeTN6TkhnLmtoZWtWaTFQSzNv

Refactoring a Real App with Agent Skills in Cursor

Icon Composer can make or break your iOS app icon. I used AI to generate an app icon in minutes… then realized it would never help me reach 10K MRR. In this episode, a professional designer rebuilds it properly using Apple’s Icon Composer. If you’re an iOS developer, your app icon isn’t decoration — it’s your front door in the App Store. In this video, I’m joined by Michael Flarup, one of the most experienced app icon designers in the industry, to break down: - Why AI-generated icons often feel “soulless” - How professionals actually think about app icon design - A real Icon Composer workflow (sketch → Photoshop → Icon Composer) - Liquid Glass, layers, groups, shadows, and real-world constraints - How to design an icon that feels premium on iOS This is a practical, honest walkthrough — not theory — showing how Icon Composer fits into a professional design process. 👍 If this helps you ship a better iOS app, like the video and subscribe to follow the full journey. CHAPTERS 0:00 – I used AI to generate my app icon 0:34 – Why app icons matter for perceived value 1:38 – Meet Michael Flarup (professional app icon designer) 6:10 – Reviewing the AI-generated icon 7:45 – The biggest problem with AI app icons 12:05 – The real app icon design process 13:30 – Research & competitive analysis 14:20 – Why “ugly sketches” matter 16:05 – From sketches to Photoshop mockups 19:45 – Exploring icon concepts & storytelling 23:31 – Introducing Icon Composer 25:10 – Liquid Glass, layers & groups explained 29:20 – Grids, alignment & Apple’s icon guidelines 31:00 – Designing for growth & narrative 35:20 – Colors, translucency & shadows 39:00 – When to DIY vs hire a designer 44:00 – Final thoughts & what’s next in the series 🚀 From App Idea to 10K MRR This video is part of my “From App Idea to 10K MRR” series, where I publicly document the journey of building a real app — from idea to sustainable revenue. No growth hacks. No fake screenshots. Just real decisions, trade-offs, and lessons learned as an indie iOS developer. Follow along if you’re building: - iOS or macOS apps - Indie products - Subscription-based software 🎨 About Michael Flarup Michael Flarup is a world-class designer known for creating high-quality app icons, games, and digital products for both indie developers and large companies. He’s also the founder of Pixelresort and Northplay, and the creator of Dino Lords. Relevant links: - https://pixelresort.com - https://flarup.shop - https://flarup.email - https://dinolords.com - https://x.com/flarup - https://instagram.com/flarup - https://youtube.com/flarup 👋 About Me I’m Antoine van der Lee — iOS developer, indie maker, and creator of SwiftLee. I build apps, teach Swift, and share everything I learn along the way: - SwiftLee Weekly newsletter (30K+ subscribers) - RocketSim — an Xcode Simulator productivity tool for iOS devs - Courses & international conference talks Subscribe to follow the journey — and avoid the mistakes I’ve already made. #IconComposer #iOSAppIcons #AppStoreDesign #IndieAppDev #iOSDeveloper
Icon Composer: A Pro Designer Rebuilds My AI App Icon (iOS 26 Liquid Glass)
YouTube Video VVViSXV4QTZNLVE5QXRLZ1FKeTN6TkhnLnNFT1BsT3lGTW9J

Icon Composer: A Pro Designer Rebuilds My AI App Icon (iOS 26 Liquid Glass)

Before you build your next app, make sure the idea can actually make money. In this episode, I break down the exact framework I use to validate profitable app ideas — long before writing any code. You’ll learn how to avoid wasting months on the wrong app idea and how to use AI, ASO tools, and market research to discover ideas with real potential. If you’re trying to go indie, hit your first 1K MRR, or build an app that grows into a business, this process will completely change how you think about “good” app ideas. WHAT YOU'LL LEARN - How to find app ideas that make money - My 8-step checklist for validating any app idea - How to test demand using ASO tools like AppFigures - How AI becomes a powerful app-idea sparring partner - Why passion & competence matter more than you think - Real examples: The two ideas I'm considering - How to match your skills with a big enough market - Why most developers quit too early — and how to avoid it CHAPTERS 0:00 – Why most developers pick the wrong app idea 0:23 – The 8 rules for a profitable app idea 3:39 – Monetization paths that actually work 4:35 – Why copying existing apps will get you rejected 5:49 – Using your audience as a competitive advantage 6:01 – Where good app ideas actually come from 7:01 – AI as your brainstorming partner 8:03 – Turning inspiration into real evaluation 10:35 – Mapping your skills & interests 12:05 – App Idea #1 13:02 – App Idea #2 14:04 – Validating ideas using ChatGPT 18:03 – Validating ideas using ASO tools 22:48 – Does a LinkedIn app idea make sense? 23:23 – Why the YouTube idea might have bigger potential 26:11 – The role of passion (and why most developers quit) 27:27 – A real example: RocketSim’s slow early growth 28:27 – Learn by shipping 28:44 – Summary & what’s next DON'T MISS OUT ON THE JOURNEY If you enjoyed this, Like & Subscribe! I’m documenting the entire journey of building a new indie app from scratch — idea to 10K MRR. Subscribe so you don’t miss the next episode where I reveal which app idea I’ll build. #appideas #profitableappideas #appideastomakemoney #buildinpublic #indiedeveloper #swiftdevelopment #iosdevelopment #swiftui #swiftlanguage
How to Find a Winning App Idea (Before You Waste Months Building the Wrong One)
YouTube Video VVViSXV4QTZNLVE5QXRLZ1FKeTN6TkhnLkxaV2FNbVRsdy1N

How to Find a Winning App Idea (Before You Waste Months Building the Wrong One)

Building fast doesn’t matter if you’re building the wrong thing. In this episode of From App Idea to 10K MRR, I slow down—on purpose—to validate whether I’m actually building something YouTube creators need, before wasting weeks shipping features nobody wants. I’ll show you my exact target audience research process, using: - AI (Custom ChatGPT projects) to analyze real user data - App Store reviews from competing YouTube creator tools - Reddit threads where creators openly share their struggles Instead of building “another YouTube Studio,” the goal is clarity: 👉 not what happened, but what to do next to grow. By the end of this video, I land on a focused MVP idea—a Daily Growth Card—and define a clear target persona to avoid becoming a copycat app. If you’re building an app, SaaS, or side project, you can reuse this process to validate direction fast—without killing momentum. LIKE & SUBSCRIBE 👍 Like this video if it helped 🔔 Subscribe to follow the full journey from idea → MVP → first users → 10K MRR CHAPTERS 0:00 – Building fast vs building right 0:34 – Learning from competitor apps 1:15 – Why I won’t build another YouTube Studio 2:45 – Mining 1-star App Store reviews 3:54 – Finding real pain points on Reddit 5:02 – Turning research into a Custom GPT project 6:44 – Asking the right questions with AI 8:24 – What creators hate about existing tools 10:25 – What creators actually want 11:35 – The real opportunity: “what should I do next?” 16:57 – The killer MVP: the Daily Growth Card 21:10 – Creating a target persona 24:10 – What’s next in the series ABOUT THIS SERIES From App Idea to 10K MRR I’m publicly building a new app from scratch and documenting every step—the good decisions, the wrong turns, and the uncomfortable trade-offs. In this series, I cover: - Validating app ideas - Audience research and positioning - Building MVPs without overbuilding - Growth, monetization, and pricing - Working toward 10K MRR in a realistic, sustainable way No hype. No “overnight success.” Just real building. ABOUT ME I’m Antoine van der Lee — iOS developer, indie maker, and creator of SwiftLee. I build apps, teach developers, and share what actually works when turning side projects into real products. SwiftLee: https://www.avanderlee.com/?utm_source=youtube&utm_medium=description&utm_campaign=appidea_to_10kmrr SwiftLee Weekly (newsletter): https://www.avanderlee.com/swiftlee-weekly/?utm_source=youtube&utm_medium=description&utm_campaign=appidea_to_10kmrr RocketSim: https://www.rocketsim.app/?utm_source=youtube&utm_medium=description&utm_campaign=appidea_to_10kmrr #targetaudience #audienceresearch #ai #indiedeveloper #buildinpublic #saas #appdevelopment #youtubecreators #startups #productdiscovery #swiftdevelopment #iosdevelopment #swiftui #swiftlanguage
How I Research My Target Audience Using AI, Reddit & App Store Reviews
YouTube Video VVViSXV4QTZNLVE5QXRLZ1FKeTN6TkhnLjRBSHJSTGlwTmt3

How I Research My Target Audience Using AI, Reddit & App Store Reviews

The Essential Swift Concurrency Course for a Seamless Swift 6 Migration.

Learn all about Swift Concurrency in my flagship course offering 13 modules, 84 lessons, videos, code examples, and an official certificate of completion.

Updated for Swift 6.2 and now available with a limited-time launch offer.

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actor associatedtype async @autoclosure available await break catch class continue defer @discardableResult @dynamicCallable @dynamicMemberLookup enum @escaping fileprivate for @globalActor guard infix isolated lazy @MainActor nonisolated optional postfix @propertyWrapper private protocol required @resultBuilder rethrows sendable some struct subscript throw throws try typealias @unchecked @unknown unowned weak where while

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Learn more about Swift

Swift Computed Property: Code Examples

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Property Wrappers in Swift explained with code examples

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Async await in Swift explained with code examples

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FREE 5-day email course: The Swift Concurrency Playbook by Antoine van der Lee

FREE 5-Day Email Course: The Swift Concurrency Playbook

A FREE 5-day email course revealing the 5 biggest mistakes iOS developers make with with async/await that lead to App Store rejections And migration projects taking months instead of days (even if you've been writing Swift for years)

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Learn SwiftUI

SwiftUI Architecture: Structure Views for Reusability and Clarity

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Build Apps Faster using RocketSim

Recommend by Apple as an “Essential Tool for Developers”, RocketSim helps thousands of engineers to save hours per week. Discover these articles and learn how you can leverage RocketSim to improve your workflow:

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Combine all the things

Combine and Swift Concurrency: A threading risk

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@Published risks and usage explained with code examples

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Dive into Core Data

How to observe NSManagedObject changes in Core Data using Combine

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Data validation on insertion, update, and deletion in Core Data

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Derived Attributes to improve Core Data Fetch Performance

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Be an expert on Xcode

The 7 changes I do for every new Xcode project

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Simulator Camera: Test your app without a physical device

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Build performance analysis for speeding up Xcode builds

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Icon Composer: Transforming an AI-generated icon

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From App Idea to 10K MRR – YouTube Series

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Testing push notifications on the iOS simulator

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Explore categories Swift Combine Concurrency SwiftUI Core Data Xcode Debugging Workflow Optimization Swift Charts Swift Testing Latest Video
Agent Skills solve one of the biggest problems with AI coding tools: consistency. In this video, I show how I use Agent Skills in Cursor to refactor a real Swift app using a Swift Concurrency skill — step by step. I’ve been using tools like Codex, Cursor, and Claude Code for a while, but I kept running into the same issue: best practices and skills lived in project-specific AGENTS files, and keeping them in sync across projects was painful. That’s where Agent Skills come in. In this video, you’ll learn: - What Agent Skills actually are (and how they differ from AGENTS files) - How to install Agent Skills once and keep them up to date - How Cursor discovers and applies Agent Skills automatically - How I use a Swift Concurrency Agent Skill to plan and refactor a real app - Why Agent Skills improve correctness, consistency, and trust when refactoring with AI This isn’t a toy example — it’s a real app, real technical debt, and a refactor that needs to be done carefully. If you’re a Swift developer using Cursor (or considering Agent Skills), this video shows how experienced developers can work with AI without giving up engineering judgment. 👍 If this video helps, consider liking it and subscribing for more deep dives into Swift, AI-assisted development, and building real apps. Subscribe to my channel here: https://www.youtube.com/@avanderlee?sub_confirmation=1 CHAPTERS 0:00 – The problem with AGENTS files across projects 0:29 – What Agent Skills are (open format overview) 1:50 – Agent Skills vs project-specific AGENTS files 3:18 – How Agent Skills are discovered and applied 4:05 – Agent Skills adoption in Cursor and other tools 4:46 – Introducing the Swift Concurrency Agent Skill 6:03 – Skill structure: entry points and references 7:45 – Why skills should be created by domain experts 8:53 – The real app we’ll refactor (context & constraints) 9:37 – Installing an Agent Skill with Open Skills 10:31 – What changes in the AGENTS file 11:12 – Planning a Swift Concurrency refactor with Cursor 13:47 – Interpreting refactor insights and priorities 14:54 – Final thoughts and next steps 🔗 References & Links Swift Concurrency Course https://www.swiftconcurrencycourse.com Swift Concurrency Agent Skill (GitHub) https://github.com/AvdLee/Swift-Concurrency-Agent-Skill Agent Skills (open format) https://agentskills.io From App Idea to 10K MRR – YouTube Playlist https://youtube.com/playlist?list=PLg4qABgFp_nRYMtGFdXz8sUeXb2IDxdPL&si=pKZosWay0bbOWjD6 ⸻ 👋 About Me I’m Antoine van der Lee — Swift developer, indie founder, and educator. I create in-depth content about Swift, Swift Concurrency, AI-assisted development, and building profitable apps as an indie developer. I run: - SwiftLee – articles read by Swift developers worldwide - SwiftLee Weekly – a weekly newsletter for Swift developers - RocketSim – a Mac developer tool app to speed up iOS development - Advanced Swift courses, including Swift Concurrency Subscribe for practical, senior-level Swift content focused on real-world apps and long-term maintainability. #AgentSkills #CursorAI #iosdevelopment #SwiftConcurrency #AIForDevelopers
Refactoring a Real App with Agent Skills in Cursor
YouTube Video VVViSXV4QTZNLVE5QXRLZ1FKeTN6TkhnLmtoZWtWaTFQSzNv

Refactoring a Real App with Agent Skills in Cursor

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