The Secret World of Phone Hackers
Like Duolingo, but for The Secret World of Phone Hackers. Tomo turns the whole topic into a game you play five minutes a day, until it actually sticks.
For the part of you with thirty open tabs that never became anything.
Free during early access · No credit card · iPhone & Android

You've tried the other tabs
Thirty open tabs. Four facts you actually kept.
You watched. You nodded. By Sunday it was gone.
One answer, then back to scrolling.
Eight weeks. You meant to finish. You didn't.
Tomo turns The Secret World of Phone Hackers into a game you actually finish. Levels, streaks, and quick quizzes that make it stick. Five minutes a day.
Where The Secret World of Phone Hackers takes you
Travel back to a time when the world's phone lines were a giant playground. Discover how early hackers used plastic whistles and homemade boxes to explore the global network for free.
- 1
The Magic of the Telephone Network
- How Calls Used to Travel
- The Secret Language of Tones
- Why the System Was Vulnerable
- The People Who Found the Holes
- 2
The Toy Whistle That Changed Everything
- The 2600 Hertz Discovery
- Captain Crunch and His Cereal Prize
- Tricking the Long Distance Lines
- The Blind Kids with Perfect Pitch
- Exploring the Tandem Switches
- The Joy of Free Long Distance
- 3
Building the Famous Little Boxes
- The Blue Box: Taking Control
- The Red Box: Faking Coins
- The Black Box: Receiving Free Calls
- 4
The Culture of the Underground
- Meeting on Secret Party Lines
- The First Hacker Magazines
- How Steve Jobs and Wozniak Started
- The Ethics of the Phone Phreaks
- The Most Famous Pranks Ever Pulled
- 5
The Law and the End of an Era
- The Phone Company Fights Back
- The FBI Gets Involved
- Moving from Tones to Computers
- The Legacy of the Golden Age
5 sections · 22 units · 88 levels. Built to play, not to enroll.
Here's what playing it feels like
A real question from this course. Take your best guess.
Imagine you lift the receiver in 1960. Where does your phone line physically terminate to begin its journey?
Get it right to open this lesson and 87 more in the app.
You pick the voice
The Secret World of Phone Hackers is taught in the The Storyteller style: every lesson is a story. Want a different feel? In the app you can spin up the same topic in any of Tomo's teaching styles. Same facts, totally different vibe.
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Start The Secret World of Phone Hackers today.
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