Module 2 — Android Integration & Background Survival

Mandatory system-level implementations to prevent the Android OS from killing the application in the background.

Tracked in #3 (service, notification, interruptions) and #4 (permissions, battery optimization).

Microphone Foreground Service

An ongoing Service declared with the mandatory foregroundServiceType="microphone" flag, tied to the app’s lifecycle. It owns the capture engine and the ring buffer, so the buffer survives Activity destruction. This is the single highest-risk failure mode of the product: without it, “the last 30 minutes” silently becomes “the last few seconds”.

Persistent Notification & Home-Screen Widget

The required status bar notification indicating active recording runs on a dedicated low-importance channel and shows the live capture state and buffered duration.

Quick action buttons on the notification let the user trigger Save (writes the buffered audio since the last save), Live (starts or stops a continuous forward recording that includes the buffered past), and Stop (stops the recording service) without opening the app. A one-tap home-screen widget (#275) also lets the user start or stop recording directly from the launcher.

Audio Interruption Handling

AudioManager.AudioRecordingCallback gracefully pauses buffer writing during incoming phone calls and resumes automatically afterward.

The pause window’s wall-clock duration is recorded, not just a flag — the export gap handler (Module 3) needs that duration to inject the right amount of silence. These two features do not work independently.

Runtime Permission Manager

The UI flow requesting RECORD_AUDIO and, on API 33+, POST_NOTIFICATIONS, with a rationale shown before the system dialog and a recovery path out of permanent denial.

Battery Optimization Bypass

A guided flow redirecting the user to ACTION_REQUEST_IGNORE_BATTERY_OPTIMIZATIONS to prevent aggressive OEM task killers (Samsung, Xiaomi) from shutting the app down. Skippable — the app stays usable, with a visible warning, for a user who declines.