#case-study: 03•Native Android Emergency System•v1.0 Released • v2.0 In Progress
WomenSafety
A native Android safety companion app engineered for instant distress dispatch during emergencies. Features hold-to-SOS panic button, background accelerometer shake detection, live GPS location sharing via SMS, fake call simulator, and one-touch calling to Bangladesh emergency hotlines (109 / 999).
#note:v1.0 release published on GitHub; v2.0 build with enhanced architecture is actively ongoing.
01.Problem & Context
During dangerous encounters or harassment situations, victims rarely have time to unlock screens, navigate complex menus, or dial conventional phone numbers.
02.System Architecture & Data Flow
Built natively with Java and Android SDK using MVVM architecture (ViewModel, LiveData), Material Components 3 UI, Firebase Authentication & Cloud Firestore for secure cloud sync, and EncryptedSharedPreferences for local security.
03.Engineering Challenges & Solutions
- Calibrating accelerometer sensor thresholds with anti-false-trigger debouncing to distinguish between running/walking and violent shake gestures.
- Reliably fetching real-time GPS coordinates via Android LocationManager and formatting instantaneous Google Maps distress SMS links.
- Engineering a realistic fake incoming call simulator to discreetly defuse uncomfortable situations.
#technologies-utilized
JavaAndroid SDKMVVMFirebaseMaterial 3GPS / Telephony