How One Developer Built a Battery-Friendly Geofencing App to Auto-Silence Phones

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A developer built an Android app called Muffle after repeatedly being disrupted by ill-timed phone notifications in quiet public spaces like lectures and mosques. The app uses Google Play Services' GeofencingClient to automatically switch a device to silent mode when the user enters a defined location, then restore sound upon exit. Rather than continuously polling GPS coordinates — which drains battery — the engine offloads location monitoring to the Android system, which uses cell towers and Wi-Fi signals for low-power proximity detection. Developers define a circular geofence with a latitude, longitude, and radius, and the system triggers the app only when a boundary is crossed. The approach trades pinpoint accuracy for battery efficiency, with a 100-metre radius deemed acceptable for managing sound profiles.

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