My UK client runs a real-money financial trading app that ships on both iOS and Android. Until a few weeks ago users everywhere could sign in without a hitch, yet logins coming from Egypt now fail at the authentication step even though nothing has changed in their credentials. The current developer has become unresponsive, so I need the issue diagnosed and resolved quickly. Scope of work • Audit the existing mobile code and any linked backend/auth services to pinpoint why Egyptian traffic is rejected or mis-handled. • Patch the root cause so users in Egypt can sign in exactly as before, without breaking access in other regions. • Regression-test the fix on the latest iOS and Android builds (I will supply TestFlight and Play Console access). • Provide a concise hand-over report describing the cause, the applied remedy, and any recommended follow-up improvements. Acceptance criteria 1. A test account I provide must log in successfully from an Egyptian IP (I will verify through a VPN and with a local tester). 2. No new authentication failures appear in other geos. 3. Your change set is pushed to our repo with clean, commented code and passes existing unit/integration tests. I’m open to additional hardening—two-factor auth, biometric login, CAPTCHA, etc.—once the immediate outage is fixed. After that, I intend to keep the right person on a monthly maintenance retainer of ₹10-11 k, so think of this as both a rescue task and a paid trial for ongoing work.