ipodderx-app

The ipodderx-rs web UI in an app, with the audio played by the phone rather than the page, so it keeps going when the screen locks and a car can control it.

Why it is not just a web view

CarPlay and Android Auto cannot render a web view. Both are template surfaces — CPListTemplate and CPNowPlayingTemplate, or Android's media browse tree — and the only audio they will control is the host's own AVPlayer or ExoPlayer. So an app that is "the web UI plus CarPlay" is really "the web UI whose audio engine is native", and that is what this is.

The page keeps its face. Everything in ipx's web/src/player.ts speaks to its media element through a small surface, so web/src/native.ts replaces that surface on the element with one that posts to this app. The player bar, the row buttons, the EQ bars and the keyboard shortcuts all work as they do in a browser, with nothing in player.ts changed. Video still plays in the page: CarPlay is audio-only, and a native video layer under a web view buys nothing.

What works, and what needs an Apple account

Plays with the screen locked	Yes, on a free personal team. UIBackgroundModes: [audio] is a plist key, not a signed entitlement
Lock screen and Control Center	Yes — MPNowPlayingInfoCenter, MPRemoteCommandCenter
A car over Bluetooth or USB audio	Yes — the head unit shows the episode and its buttons drive the app
CarPlay's own app on the dashboard	No. com.apple.developer.carplay-audio is granted by Apple on request and does not exist on a free team

A free personal team also expires a build after seven days, so it is reinstalled from Xcode weekly, and allows three apps at a time. $99/yr makes that a year and adds TestFlight; CarPlay additionally needs a granted entitlement request at https://developer.apple.com/carplay/.

Playback and Library deliberately know nothing about the web view. A CarPlay scene is a CPTemplateApplicationSceneDelegate over the same two objects, plus a browse tree built from GET /api/feeds and GET /api/entries — no change to this app's shape or to the server.

Build it

brew install xcodegen
cd ios && xcodegen generate
open iPodderX.xcodeproj

Pick a destination and run. My Mac (Mac Catalyst) is one of them: the same UIKit app in a window, built from the same target. Nothing in the Swift is conditional -- AVAudioSession, MPNowPlayingInfoCenter and the remote commands all exist under Catalyst -- so the Mac gets media keys and Now Playing in Control Center for free. It has no CarPlay and no lock screen, which is most of the point on a phone, so the Mac build is a convenience rather than the reason any of this exists.

SUPPORTS_MACCATALYST is set as a build setting rather than through xcodegen's supportsMacCatalyst:, which this version accepts and then writes nothing for -- the generated project had no such setting and the Mac destination simply did not exist.

Set your team under Signing & Capabilities, pick your phone, and run. The project is generated from project.yml, so .xcodeproj is not in git — edit the yml, not the project.

Which server

The first launch asks, with https://ipodderx.sdf1.net filled in. A bare host gets https://, so typing ipodderx.sdf1.net is enough. Then sign in on the page that follows — through Cloudflare Access, or ipx's own form — and the cookies that leaves are what the player uses.

Shake the phone to change it, or tap Server in the red banner when something is wrong. There is no button in the chrome because there is no chrome: the page fills the screen, and this is a setting touched about once.

Plain http:// is allowed only on your own network — localhost, *.local, and the private ranges — which is what NSAllowsLocalNetworking covers. The setup screen says so as you type rather than letting the load fail later looking like the server is down.

For automation, -ipx.server <url> as a launch argument overrides the stored value for that run.

How it hangs together

ios/Sources/App.swift	the app delegate, and which scene is which
ios/Sources/SceneDelegate.swift	the window. iOS 27 will not run an app without a scene, and CarPlay is a second one
ios/Sources/ServerSetupViewController.swift	the first-run question, and the way back to it
ios/Sources/WebViewController.swift	the WKWebView, and the banner when something is wrong
ios/Sources/Bridge.swift	the messages, both directions
ios/Sources/Playback.swift	AVPlayer, the audio session, now-playing, the remote commands
ios/Sources/Library.swift	the API calls the host makes: position, read, artwork
ios/Sources/CookieBridge.swift	WKHTTPCookieStore into HTTPCookieStorage.shared
ios/Sources/ServerSettings.swift	which server

Authentication

ipx authenticates by cookie: ipx_session from its own sign-in, and CF_Authorization from Cloudflare Access in front of the tunnel. Its auth layer was written that way so a plain <audio src> would work, which is why the player needs no API of its own — but AVPlayer and URLSession read HTTPCookieStorage.shared while WKWebView keeps its own store, so CookieBridge keeps the two in step and passes them to each asset as AVURLAssetHTTPCookiesKey.

ponytail: when the Access cookie expires mid-drive, playback 401s and the fix is to open the app and sign in again. The upgrade is per-user device tokens in ipx's auth layer, at which point this app holds a token in the keychain and stops depending on the web view's session.

The messages

Page to host, on webkit.messageHandlers.ipx:

{t:"ready", version, rate, volume}	the bridge installed; the app waits for this before trusting the page
{t:"load", url, enc, feedId, guid, title, feedTitle, artwork, position, duration, rate, volume}	the element's src was set to an audio file
{t:"play"} {t:"pause"} {t:"stop"}
{t:"seek", to} {t:"rate", v} {t:"volume", v}
{t:"position", url}	save where we are — the page sends the path, not a time, because a backgrounded web view's time may be minutes old

Host to page, as window.ipxNative.on(…):

{t:"time", cur, dur}	drives timeupdate
{t:"meta", dur}	the length is known; the page seeks to where you left off
{t:"state", playing}	drives play / pause
{t:"ended"}
{t:"error", message}	the page toasts it

position and duration in load are for the car's display. Where playback starts is the page's decision, on loadedmetadata, so one piece of code owns it.

Position and read are written by the host, not the page: ipx's player.ts has been bitten before by a stale write — "one left paused in another tab saved its older place as that tab reloaded, over where you had got to since" — and a backgrounded web view is exactly that tab.

Changing the bridge

The page's half lives in ipodderx-rs at web/src/native.ts, and tests/native-bridge.js there is what holds the two ends together. A change to the protocol is a change in both repos and a deploy of the server before the app will work.

Layout

ios/         the Xcode project: iPhone, iPad and Mac Catalyst from one target
android/     not started

Named for what it is rather than one platform, because the half of the bridge that lives in the page already has a branch for Android (window.ipxAndroid) and there is no sense renaming later.

Android

Not started. The shape is the same — WebView for the page, Media3 MediaLibraryService and ExoPlayer for the audio, automotive_app_desc.xml for Android Auto — and native.ts already has the detection branch for it (window.ipxAndroid.postMessage). Android Auto needs no approval: sideload, and turn on unknown sources in Android Auto's developer settings.