App Design Lab: UI/UX Practice

Learn interface rules by doing

Only for iPhone

Free · In‑App Purchases · Designed for iPhone. Not verified for macOS.

iPhone

Where should a toolbar button go? How should delete work? Use screens that get it wrong, note what feels off, and compare with the fix until good UI/UX calls feel easy. Great UI/UX is a stack of small decisions. App Design Lab is a hands-on workbook where you use screens that get those decisions wrong, then see exactly why. Each lesson tackles one decision in five steps: try a broken screen, write what felt off, see why, compare it with the fix, and write down what you learned. 23 HANDS-ON LESSONS Try it: a sample app opens at full size with a task. The screen you are using breaks a rule on purpose. Write it down: before you see the answer, note what you noticed. See why: the decision, the reasoning behind it, and what falls apart if you flip it, right next to what you wrote. Compare: switch between the broken screen and the fixed one in the same spot and spot the difference. Write what you learned: keep one sentence you can reuse next time. Your notes collect in the Notes tab, where you can copy them or export them as a Markdown file. A LIBRARY FOR GOING DEEPER 68 topics: toolbars, titles, search, tab bars, sheets, and text, each drawn as a mockup. Tap any part of the picture to see the rule behind it, and open a live example screen for every topic. 100 mistakes: what was done, why it seemed right at the time, and what changes once it is fixed, written as short retrospectives. 7 principles: the core judgments behind all 68 topics, shown by flipping the same screen between a broken and a correct layout. 5 labs: adjust toolbar placement, scroll edge effects, text truncation, tab bar setup, and sheet height, and get a verdict in real time. Quiz: 396 questions that ask you to look at a screen and make the call. MADE FOR Developers who want a reason behind every button they place Designers who want to get comfortable with the latest toolbars, tab bars, and sheets Teams who need to explain the why in design reviews Try 3 lessons, 10 mistakes, the toolbar lab, and the first quiz chapter for free. The 68 topics, 7 principles, and your notes are always free. A weekly subscription, a monthly subscription, or a one-time lifetime purchase unlocks every lesson and resource. Subscriptions renew automatically at the same price unless canceled at least 24 hours before the period ends. Manage or cancel anytime in your App Store account settings. Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ There is no account, and your progress and notes stay on your device. The whole app is available in English, Japanese, and Korean.

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Easier with VoiceOver and larger text. Clearer buttons and text in Dark Mode. Open your study notes from search. Your progress is backed up every day.

Version 1.0.7

The developer, hyunho lee, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .

  • Data Not Collected

    The developer does not collect any data from this app.

    Privacy practices may vary, for example, based on the features you use or your age. Learn More

    The developer indicated that this app supports the following accessibility features. Learn More

    • Supported Features

      • VoiceOver

      • Voice Control

      • Larger Text

      • Dark Interface

      • Differentiate Without Color Alone

      • Sufficient Contrast

      • Reduced Motion

    Information

    Seller
    hyunho lee
    Size
    37.8 MB
    Category
    Lifestyle
    Compatibility
    Requires iOS 26.0 or later.
    • iPhone
      Requires iOS 26.0 or later.
    • Mac
      Requires macOS 26.0 or later and a Mac with Apple M1 chip or later.
    • Apple Vision
      Requires visionOS 26.0 or later.
    Languages
    English and 22 more
    • English, Czech, Danish, Dutch, Finnish, French, German, Greek, Indonesian, Italian, Japanese, Korean, Norwegian Bokmål, Polish, Portuguese, Russian, Simplified Chinese, Spanish, Swedish, Thai, Traditional Chinese, Turkish, Vietnamese
    Age Rating
    4+
    In-App Purchases
    Yes
    • App Design Lab Pro $39.99
    • Small Tip $0.99
    • Medium Tip $2.99
    • Large Tip $9.99
    • Pro Monthly $5.99
    • Pro Weekly $1.99
    • Learn More
    Copyright
    © LEEO 2026
  • Developer Website
  • Privacy Policy

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