android-walkthrough-video

Turns driving an app into a captioned MP4: screenrecord captures the screen, you stamp an explanation card at each beat while it happens, and ffmpeg burns the cards in afterwards. scripts/walkthrough.py runs the three phases.

The constraint that shapes everything: you cannot inject an overlay into a third-party Android app the way a web recorder injects DOM into a page. So cards are composited post-hoc against a timeline captured live — which is why mark exists instead of a scenario file with guessed timings.

When NOT to use

• A still screenshot, or tap/read/assert → android-ui-driver (this skill drives nothing; you drive with that one while recording).
• A written review with evidence → android-app-review.
• Getting the app onto the device → play-store-app-install.
• Recording a web app → that is a browser-recorder job, not adb.
• Generic video editing or format conversion → plain ffmpeg.