Docs: add the iOS (TestFlight beta) companion app alongside the Android one

Jonathan Schuster's iOS client (iPhone/iPad) is in TestFlight beta — linked in the GitHub README and
the bundled manual next to the existing Android app, framed the same way (separate community project,
speaks the same protocol, not maintained by us).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

MANUAL.md

@@ -52,6 +52,8 @@ There is no central server, no account, and nothing stored online. The sound goe
 
 > **RemSound on Android (receiver):** there is a companion app that lets a phone or tablet _receive_ RemSound audio — handy for listening on the move. It's a separate community project built and maintained by Aryan Choudhary, who is a screen-reader user himself and has tuned the app for TalkBack; it is not part of RemSound and is not maintained by us. Get the signed app from its releases page (download the latest **app-release.apk**): [RemSound Android — Releases](https://github.com/aryanchoudharypro/RemSoundAndroid/releases).
 
+> **RemSound on iOS (beta):** there is also a companion app for iPhone and iPad, currently in beta testing on Apple's TestFlight. Like the Android app it's a separate community project — built and maintained by Jonathan Schuster — and is not part of RemSound and not maintained by us, but it speaks the same protocol. Join the beta here: [RemSound for iOS on TestFlight](https://testflight.apple.com/join/pNCnj3z2).
+
 ## 2. Quick start
 
 > **If RemSound won't start** — if Windows says it needs “.NET” — RemSound runs on the **Microsoft .NET 10 Desktop Runtime**. Most up-to-date Windows machines already have it; if yours doesn't, open the **Install Scripts** folder sitting next to `RemSound.exe` and double-click **Install .NET for RemSound.cmd**. It fetches and installs it for you (using winget, the Windows package manager), and then RemSound will start. There's a `.ps1` version in the same folder for PowerShell users. If you'd rather do it by hand, the script opens Microsoft's download page, where you pick “.NET Desktop Runtime” for “x64”.

README.md

@@ -59,6 +59,12 @@ There's a companion **Android receiver**, so a phone or tablet can pick up RemSo
 
 **Get it:** [RemSound Android — Releases](https://github.com/aryanchoudharypro/RemSoundAndroid/releases) — download the latest `app-release.apk`.
 
+## RemSound on iOS
+
+There's also a companion app for **iPhone and iPad**, currently in beta on Apple's **TestFlight**. Like the Android app it's a separate community project — built and maintained by **[Jonathan Schuster](https://github.com/jonathans859)** — and isn't part of RemSound or maintained by us, but it speaks the same protocol.
+
+**Join the beta:** [RemSound for iOS on TestFlight](https://testflight.apple.com/join/pNCnj3z2)
+
 ## Learn how to use it
 
 The full user manual is right here on GitHub: **[Read the user manual](MANUAL.md)**. It covers getting connected for the first time, every setting and what it does, troubleshooting tips, and a glossary at the end. It's the same manual you can press F1 to read from inside RemSound, so you can read it before installing if you want to see what you're getting.

readme.html

@@ -73,6 +73,10 @@ ul, ol { padding-left: 1.4em; }
 <strong>RemSound on Android (receiver):</strong> there is a companion app that lets a phone or tablet <em>receive</em> RemSound audio &mdash; handy for listening on the move. It's a separate community project built and maintained by Aryan Choudhary, who is a screen-reader user himself and has tuned the app for TalkBack; it is not part of RemSound and is not maintained by us. Get the signed app from its releases page (download the latest <strong>app-release.apk</strong>): <a href="https://github.com/aryanchoudharypro/RemSoundAndroid/releases">RemSound Android &mdash; Releases</a>.
 </div>
 
+<div class="note">
+<strong>RemSound on iOS (beta):</strong> there is also a companion app for iPhone and iPad, currently in beta testing on Apple's TestFlight. Like the Android app it's a separate community project &mdash; built and maintained by Jonathan Schuster &mdash; and is not part of RemSound and not maintained by us, but it speaks the same protocol. Join the beta here: <a href="https://testflight.apple.com/join/pNCnj3z2">RemSound for iOS on TestFlight</a>.
+</div>
+
 <h2 id="quick-start">2. Quick start</h2>
 
 <div class="note">