[payamb]

iPlayer on TV (across all platforms) is a generic web application, topped with a custom wrapper app (think webview) for each platform, responsible to hook platform’s native APIs to Web/JS APIs.

I’m guessing there are some complications hooking Apple TV’s native subtitles APIs to relevant web APIs, and low usage statistics doesn’t help prioritising fixing the issue. Although the rumour is that they are working on a completely new Apple TV app.

[dbbk]

For most platforms this is true, but not Apple TV. I don't think they even allow it. iPlayer is definitely native code.

[fredoralive]

I think Apple must allow it, either that or Google have tried really hard to capture in native code the "shitty non-native web app" feel with the YouTube app. But the iPlayer app does feel fairly native.