Monsters of the Deep
Like Duolingo, but for Monsters of the Deep. 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.
A short one: 9 levels across 2 sections, about 18 minutes end to end, roughly 4 days at five minutes a day. It moves through The Famous Fangs and Hidden Dangers. It starts from scratch.
Free forever · No credit card · iPhone & Android

Key ideas in Monsters of the Deep
- A shark's dark back blends into the dark ocean floor when viewed from above
- Sharks can sense the tiny electrical pulses of a heartbeat
- A shark's white belly blends into the bright surface light when viewed from below
- Electroreception works through specialized pores on the shark's snout
- How countershading provides camouflage from different perspectives
- The function of electroreception in finding hidden prey
- Serrated edges allow sharks to 'saw' off pieces of large prey
- Sharks are naturally cautious and usually avoid unfamiliar things like humans
- Different shark species have teeth specialized for their specific diet
- Most shark bites are 'test bites' because the shark is confused or curious, not hunting
- Matching tooth shapes to their specific hunting function
- Sharks lack eyelids like humans but have a protective third eyelid
- The membrane protects the eye from the thrashing of prey during a hunt
- Understanding shark behavior and their relationship with humans
- The purpose of the protective eye membrane during an attack
- Light is extremely rare in the deep ocean
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 gives Monsters of the Deep the Duolingo treatment: levels, streaks, and quick quizzes that test what you just learned. That game loop is what the tabs above never had, so it's the one you actually finish.
Here's what playing it feels like
A real question from this course. Take your best guess.
How can a shark find a fish that is perfectly still and hidden under the sand?
Get it right to open this lesson and 8 more in the app.
Where Monsters of the Deep takes you
Unmask the ocean's most terrifying residents and discover the survival secrets behind their nightmare-inducing looks.
- 1
The Famous Fangs
- The Sharks in the Room
- Nightmares of the Midnight Zone
- 2
Hidden Dangers
- Small, Silent, and Deadly
2 sections · 3 units · 9 levels. Built to play, not to enroll.
You pick the voice
Monsters of the Deep is taught in the The Bestie style: your friend who just gets it. 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 Monsters of the Deep today.
Download Tomo, search Monsters of the Deep, and play your first lesson in under a minute.