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AudraThe personal safety app that works when your screen is locked and your hands are full

By Kenneth Melchor, Founder & Technology Director

2026
iOS App DevelopmentFirebase BackendCloud Infrastructure
SwiftSwiftUIwatchOSFirebaseAWS SNSApp Store
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This case study covers Audra — a native iOS personal safety app for women. One gesture triggers a simultaneous emergency response: loud siren, continuous audio recording, real-time GPS tracking, SMS to emergency contacts with a live location link, and optional auto-call to police — all running in the background with the screen locked. Responders receive a live web page with a real-time map and a freshness badge.


Existing safety apps fail at the moment they matter most — they require a screen tap, a passcode, a moment of calm. Audra was built for the opposite: phone in a pocket, one hand free, under stress. Every feature had to work silently in the background with the screen locked. Apple's background execution budget is narrow; a data race in an audio session kills the alarm silently. Getting Apple's Critical Alerts entitlement — which bypasses Do Not Disturb on responder devices — required a manual approval process with strict criteria.

Audra — The Challenge

10 Independent SOS Trigger Paths (button, widget, voice, volume combo, Apple Watch, fall detection)5 Simultaneous Evidence Streams (audio, video, screenshot, GPS trail, network forensics)AES-GCM On-Device Encryption via CryptoKit — Firebase never holds plaintextReal-Time Responder Web Page with Live GPS Map and Freshness BadgeAWS SNS SMS — 113-char single message across GB/ES/FR/DEApple Critical Alerts Entitlement — bypasses Do Not Disturb on responder deviceswatchOS Companion + WidgetKit Lock Screen Widget24-Country Emergency Number Auto-Dial Database
Audra — 10 Independent SOS Trigger Paths (button, widget, voice, volume combo, Apple Watch, fall detection)Audra — 5 Simultaneous Evidence Streams (audio, video, screenshot, GPS trail, network forensics)Audra — AES-GCM On-Device Encryption via CryptoKit — Firebase never holds plaintextAudra — Real-Time Responder Web Page with Live GPS Map and Freshness Badge

Every architectural decision was made under one constraint: it must work when someone's life depends on it. 10 trigger paths. 5 evidence streams. One gesture.


10

Independent SOS trigger paths — no single point of failure

5

Simultaneous evidence streams per SOS event

24

Countries with auto-dial emergency number

10

Locales supported at launch


100Speed
100Accessibility
100Best Practices
100Search
Live & maintainedSEO optimised

Mobile · Google PageSpeed Insights


97+

Lighthouse score on kaufast.com across all four categories — verified via Google PageSpeed Insights, June 2026

20+

Years delivering technology solutions — founded in Barcelona, 2004

50+

Projects delivered across 6 countries and 3 continents

< 100ms

Time to First Byte via Vercel Edge Network — every managed project, worldwide

All metrics independently verifiable. Last audited June 2026.


Services Delivered

  • iOS App Development
  • Firebase Backend Architecture
  • Cloud Infrastructure
  • App Store Submission Pipeline
Services

Technologies

  • Swift 6
  • SwiftUI
  • watchOS
  • WidgetKit
  • AVFoundation
  • SFSpeechRecognizer
  • CryptoKit
  • CoreLocation
  • Firebase (Auth, Firestore, RTDB, Storage)
  • Cloud Functions (TypeScript)
  • AWS SNS
  • StoreKit 2
  • Fastlane
  • Leaflet.js

Team

  • iOS & watchOS Engineer
  • Backend & Cloud Architect
  • UX Designer
  • App Store Submission Lead
  • QA & Safety Testing

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