How Product Managers Can Adapt Apps for iPhone Duo with Duology AI Skills

01 What This Skill Pack Does for Product Managers

Duology packages adaptation knowledge, layout solutions, and review workflows into AI-callable skills. Once integrated into a supported coding tool, the AI can invoke these skills automatically or on demand. For product managers, the most direct use is turning "adapt to foldable" into concrete, reviewable, implementable, and verifiable requirements.

Writing requirements: Define page behavior for each posture — closed, fully open, half-folded (book), and tabletop — so content and action entry points change explicitly.

Design reviews: Check whether expanded views warrant extra detail panels, whether folded areas obscure primary content, and whether navigation and toolbars remain discoverable after layout shifts.

Acceptance testing: Verify that user tasks survive posture changes — reading position, playback progress, input drafts, selected items, and back-stack — rather than just confirming the page renders.

02 Key Capabilities of Duology (v0.3, 2026-10-21)

The README lists 30 skills across 5 plugins covering basic adaptation, design interaction, app recipes, test checks, and iOS 27 features. Verification so far uses Xcode 27.1 and the Duo simulator; real-device and public test results are pending.

Layout Patterns & State Continuity

Curated patterns include list-detail, side panel, and dual-page reading, plus guidance on preserving state during fold, unfold, rotation, and window-size changes. This helps teams discuss "what to show when the screen grows" and "what to keep during the transition" together.

Reference App Recipes

Five starter recipes: two-player game, finance dashboard, media player, reader, and store. A reading product can use the reader recipe to debate body-text vs. notes side-by-side; a media product can use the player recipe to decide how video and controls split in tabletop mode. These are discussion starters, not final specs.

Code Lint & Posture Review

duo-lint

flags unsuitable layout code. Posture screenshot and design-review skills check closed, open, book, and tabletop states. For PMs, this expands acceptance from a single screenshot to a matrix of real usage scenarios.

Note: Duology is a community project independent of Apple. Skills provide guidance and checks; generated solutions must still be validated in the project environment.

03 Download & Installation

Quick content preview: Open the GitHub repo, read the README, then browse the skills directory. To save source, use Code → Download ZIP and configure per your tool's instructions.

Claude Code: Run the following slash commands to add the marketplace and install the core plugin:

/plugin marketplace add Kimeur/duology
/plugin install duology@duology

Optional plugins for design review, recipes, ship checks, and iOS 27 features:

/plugin install duology-design@duology
/plugin install duology-recipes@duology
/plugin install duology-ship@duology
/plugin install duology-features@duology

Restart Claude Code, then run /duo-doctor to verify the environment (Apple silicon Mac, Xcode 27.1, simulator runtime).

Cursor, Codex, Copilot, etc.: In a terminal with Node.js and npx: npx skills add Kimeur/duology Follow the installer prompts to pick target tool and scope. This installs skills only; Claude Code slash commands and lint hooks do not fully migrate. With other tools, invoke skills via natural language prompts.

04 Try It on One High-Frequency Page First

Pick a core page — e.g., article reader, product detail, or video player. Feed the AI the business goal, current page, and must-keep state to get discussable output.

Example prompt (adapt to your project):

Use the installed Duo adaptation skills to audit the article reading page. Describe layouts for closed, fully open, book, and tabletop postures. Focus on body-text vs. notes relationship, primary action placement, and whether reading position, annotation drafts, and navigation state survive switches. Output issue list, fix suggestions, and acceptance cases; then verify in simulator or device and mark incomplete tests.

Four concrete acceptance actions: 1. Read to a passage → unfold → check content/state/entry points. 2. Enter annotation → fold to outer screen → verify draft retained. 3. Switch posture → continue paging → ensure position held. 4. Return to table of contents → re-enter article → confirm deep link works.

This scoped trial lets the team evaluate rollout for remaining pages.

05 Related Projects to Bookmark

iphone-duo-adaptive-ui (bahimzabir) — Targets SwiftUI/UIKit, based on Apple HIG, six Tech Talks, and dev docs. Flags unconfirmed info. Current re-check version v0.2.0 (2026-09-22); cross-reference with latest SDK before using API examples.

github.com/bahimzabir/iphone-duo-adaptive-ui
npx skills add bahimzabir/iphone-duo-adaptive-ui

kaissaroj/iphone-duo-skills — Covers SwiftUI, UIKit, React Native, Expo with unified skill install.

github.com/kaissaroj/iphone-duo-skills
npx skills add kaissaroj/iphone-duo-skills

mirzaaghazadeh/iphone-duo-skills — Lets you pick skills by stack: native layout, camera, design review, plus React Native, Expo, Flutter. Cross-platform integration depends on your framework and native bridge.

github.com/mirzaaghazadeh/iphone-duo-skills
npx skills add mirzaaghazadeh/iphone-duo-skills

twostraws/Swift-Agent-Skills — General Swift skill navigation.

AvdLee/SwiftUI-Agent-Skill — Reference index includes iphone-duo.md alongside SwiftUI best practices.

github.com/twostraws/Swift-Agent-Skills
github.com/AvdLee/SwiftUI-Agent-Skill

06 Don't Miss Apple's Official Check Entry

Apple's Duo adaptation guide now exposes an App Resizability skill. In Xcode, ask the coding assistant to scan for adaptation issues. For other tools, export the skill via: xcrun agent skills export Run in a Mac terminal with the Xcode toolchain, then configure the exported skill in your editor. Suggested workflow: use Apple's official skill for baseline layout checks, then layer community skills for design recipes and scenario reviews.

Bottom line: If you own an iOS product, share Duology with design and engineering today. Start with one core page: what extra info appears when unfolded, what state persists when folded, what action the user needs next. Write those answers into requirements and acceptance cases — that's when the skill pack becomes part of the product process.