Blackout
One switch sends your chosen contacts a calm heads up by text, with an undo window. If the phone dies, calls can forward to a number that tells trusted callers your last known location.
Period
- Jul 2026
Role
- Sole engineer
Type
- iOS app
Tools
The problem
You're out at night with 4% battery. Either you go quiet and people worry, or you burn what's left texting everyone. Blackout handles both cases.
Two modes
Blackout mode is for when you're saving battery. Flip one switch and each person you picked gets a short text with your plan, and you can write a different first line for each one. There's a ten second undo in case it got flipped in your pocket.
Beacon mode is for when the phone is about to die. It doesn't text anyone. It quietly sends low power location updates, and once the phone is dead, your carrier's call forwarding sends missed calls to a Twilio number. People on your list hear your last known location and plan and get a map link by text. Anyone else gets a generic message.
Design choices
A dead phone can't run code, so everything that happens after it dies lives with the carrier and the server. There are no accounts. Contacts stay on the phone and only leave it inside a flip. Each session gets a private owner token and a separate public status link that expires a day after you're back. Every time shown reads "last confirmed," and data deletes itself after a week. The Twilio webhook checks signatures and rejects anything it can't verify.
Status
The backend is FastAPI with 36 tests, and the app is SwiftUI with unit and UI tests, including one that drives the whole flip flow against a local server. It's not deployed, and the beacon and voice parts are still in progress.