What's New

- Added a message in case your iPhone is muted and you don't get sound
- Updated to be compatible with latest version of iOS

App Description

Note: Your device must have a flash to use this app!

Camper, Sailor, Soldier, Spy

A handy tool for campers, scouts, boaters, (and yes, spies)!

Use it to communicate with distant friends using Morse code, tap out a beat for a human-powered strobe light, or get the attention of rescuers.


This app is based on the old mechanical “signal lamp” which is a manually-controled shuttered spotlight used on warships to communicate securely while maintaining radio silence.

Modern navies still use signal lamps, but now use infrared wavelengths and night vision goggles!

Extra fun:

Put a paper towel tube on the flash to make a tight spotlight and you’ve got a line-of-sight communication tool that only you and your partner can see.

p.s. SOS is . . . – – – . . .

iPhone Screenshots

(click to enlarge)

Signal Light screenshot 1 Signal Light screenshot 2

App Changes

  • November 15, 2015 Initial release
  • March 08, 2016 New version 1.0.1
  • June 13, 2019 New version 1.0.3
  • September 16, 2023 New version 1.0.4

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