Steamworks SDK 1.63 has been released – Added libs for linuxarm64 and androidarm64
(store.steampowered.com)
Sounds like they’re leaving the option open for Android developers to make their APK distributions compatible with Steam to play on Frame.
It was first reported months ago that Valve is involved with Waydroid (Android app compatibility for Linux with Wayland) and then at the Frame announcement confirmed to ship on Frame.
This could also potentially mean that Steam itself comes to Android (at least in the EU) to allow cross-buy and cross-progression.