DuoAppsAbout DuoApps
DuoApps is an open knowledge base on designing apps for iPhone Duo, whatever the app. Written by the design team that signs every page, it’s free to reuse, with a credit to the page. The name dates from 2009; it’s back for this new iPhone.
What it is
DuoApps is the GoodBarber design team’s knowledge base on iPhone Duo, the foldable iPhone Apple introduced on September 9, 2026. It brings together two things: patterns, each one a layout question with its rule and its demo; and case studies, what Apple shows, app by app, described without a verdict.
It applies to any app, whatever tool builds it: the demos show a generic app, and the case studies the apps Apple features.
It’s published openly: its text, visuals, and demos are free to reuse and adapt, with a credit to the page (License). Anyone can also submit a pattern.
What you’ll find here
We publish what Apple says publicly about iPhone Duo, rephrased and sourced (guidelines, developer article, Tech Talks, newsroom, product page), and the team’s own design recommendations, signed as such.
Every rule line says where it comes from: Apple when Apple says it, with a link to the passage and, for a video, the timecode; Recommendation when it’s a DuoApps recommendation, with what supports it at Apple, or a note that nothing does; Hypothesis, on question pages only, for what we put forward without the source showing it.
Every page says when it was last checked, and for which version of iOS.
We publish nothing measured on prerelease tools: until the final version of Xcode 27.1 ships, no measurement or screenshot made with its beta versions goes on the site.
The story of the name
- 2009
DuoApps is founded. With Webzine Maker, the publisher of WMaker (a website builder), it starts offering app-building services.
The DuoApps website, 2009. - 2010
DuoApps and Webzine Maker launch apps.wmaker.net, a first app builder: it turns a WMaker site into a native mobile app.
- 2011
DuoApps and Webzine Maker launch GoodBarber together, an app-building service. The DuoApps trade name is gradually set aside in favor of GoodBarber.
- 2019
A merger under the GoodBarber name: Webzine Maker absorbs DuoApps and takes the name of the product launched in 2011. WMaker remains a separate product, still published.
- 2026
Apple introduces iPhone Duo on September 9. The DuoApps name, which already says what it’s about, comes back for this open knowledge base on designing apps for the new iPhone.
Who writes it
DuoApps is written by the design team at GoodBarber, an app-building service. To learn more about the company: About GoodBarber.