Architecting a background service for reliable geofencing without battery drain

Opening hook The silence in the lecture hall was heavy, the kind of stillness that only exists when a professor is deep into a complex derivation. I had my phone tucked away in my bag, confident it was silenced. Then, a sharp, upbeat ringtone cut through the quiet like a knife. It was mine. My cheeks burned as I scrambled to silence the device, but the damage was already done. The entire room turned, and the flow of the lecture was shattered. That exact moment of public embarrassment was the day I decided to stop relying on my own memory and start building a better way. The problem We live in a world where context-switching is constant. We move from the office to the gym, from the mosque to the grocery store, and from a quiet library to a noisy commute. Each of these environments demands a different sound profile, yet our phones still rely on us to manually toggle switches. The friction here isn't just about the three seconds it takes to hit the volume rocker; it