The problem
Casual games often gate rewards behind luck (gacha) or stamina timers. I wanted a collection game where what you own is exactly what you earned with your hands.
Who it's for
Mobile players who enjoy short, replayable reflex and observation challenges, and who like collecting and visual polish. The app is available in English and Japanese.
What it does
Tamor is a gem-collecting game for iPhone with four gems and four mini-games:
- Diamond, Glass Break: tap each red dot before time runs out to break through thick glass.
- Ruby, Glass Trace: follow a moving dot with your finger; three cracks end the run.
- Sapphire, Kurukuru World: find and tap pairs of gems that spin the same way.
- Obsidian, Crusher Room: break as many glass plates as you can in 10 seconds; hitting the glowing weak point scores higher.
Each result awards a gem whose carat weight (0.10 to 20.00 ct) reflects how well you played. Gems sit on a ring of twelve pedestals; tap one to inspect it in a spotlight and rotate it. Progress is stored on the device.
How it makes money (RevenueCat)
Tamor is free to download. Depths 1-3 (up to 3.00 ct) are free forever. One non-consumable purchase, World 1 Full Depth, unlocks access to Depths 4-6. It never sells gems: the 20.00 ct gem still needs clearing earlier depths and three consecutive S grades. No ads, no stamina, no random draws.
RevenueCat handles the purchase layer: the Offering and localized price, the world1_full_depth entitlement, live entitlement updates (purchase, offer-code redemption, refund), and Restore Purchases.
What makes it different
- Carats come from skill, not chance. Money buys a range of challenge, not outcomes.
- Real-time Metal rendering: refraction and color absorption inside the gems, window light, and cracking, shattering glass.
- Four distinct skill checks in one collection loop.
Categories I'm entering
Best Game (primary) and Design Award.
Inspiration and build story
In early September, Apple announced the iPhone 18 with the A20 chip, with a stronger GPU and Neural Engine. That launch inspired me to see how beautiful I could make a gem on a phone. I built a gem rendering engine in Metal, and Tamor grew around it. On supported newer iPhones you can switch on ray tracing for the selected gem.
Challenges
I designed the visuals for the newest chips, then had to make them run on much weaker ones. Most of the work was deciding what to thin out: fewer glass fragments, particles and reflections on lower-power devices, while keeping the rules, timing, hit-testing and rewards identical. A gem earned on an old phone is worth the same as one earned on a new phone. I tested on an iPhone 12 mini as my low-end device.
What I learned
Rich rendering and broad device support are a design problem, not a last-minute optimization. For a paid unlock, verifying purchase and restore on a real store build matters more than any mock.
What's next
More gems and a second world, plus richer ray-traced effects as more devices support them.
Judge access
Free offer code SHIPATON2026 (redeem link is in the Additional info section).
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