YAML Tools isn't optimized for iPhone Duo yet: version 4.1 (Jul 14, 2026) predates the iOS 27 SDK, so it runs letterboxed. Checked automatically on Nov 10, 2026.
How the status was checked
- Automatic check
- Every day, from Apple's App Store data: the version, its date, and whether the listing has screenshots made for the Duo.
- Duo screenshots
- None on the current version.
- Hand test
- Not tested on a real iPhone Duo yet. A hand test covers five postures: cover, open, laptop, book and tent. How we test
Apple hasn't published the date it started taking iOS 27 SDK builds; we use Sep 1, 2026, early on purpose, until it does.
Version and badge history
| Date | Version | What changed |
|---|---|---|
| 4.1 | First check: no iPhone Duo screenshots | |
| 4.1 | Status: Letterboxed | |
| 4.1 | First seen (version 4.1) |