Inspiration
Ice-slide puzzles are satisfying because you can't stop halfway: you slide until you hit something. We wanted a twist that makes that single rule deep for hundreds of levels. The answer was time. What if the route you just took could become the wall you need?
What it does
You are a small courier cube delivering parcels across isometric neon boards.
- Slide: swipe in any direction and the courier slides until it bumps into something.
- Rewind: tap Rewind to jump back to the start. The path you just travelled freezes into a purple shadow wall. On the next run you can stop against your own past.
- Shadows interact with the world: a shadow parked on a button keeps its door open, shadows stack, portals redirect slides, and later chapters mix all of it into paradox puzzles.
- Three stars per level: Delivered, On Time (match the par moves) and Full Cargo (collect every parcel).
- 350 levels in 14 chapters. Every level ships with a three-star solution found by the game's own solver, so nothing is unsolvable.
- Collection: earn coins by clearing levels and draw from 28 courier skins, 10 habitat backgrounds and 10 slide trails. Odds are public and draws never repeat.
- Everywhere: iPhone and native full-screen iPad, five languages (English, Traditional Chinese, Simplified Chinese, Japanese, Korean), Game Center leaderboards and 29 achievements, fully offline, no timers and no energy.
How we built it
- Native Swift and SwiftUI. The whole board is drawn in a SwiftUI Canvas with a custom isometric projection, neon glow primitives and a per-element "stage clock" that assembles every level tile by tile.
- A pure-Swift game core (engine, solver, level data) shared by the app and 140+ unit tests. The solver verifies all 350 levels and powers in-game hints.
- An Android port in Kotlin and Jetpack Compose mirrors the same core rules.
- RevenueCat handles every purchase: a one-time Remove Ads (Pro) entitlement and two coin packs, with offerings, entitlements and Google Play real-time notifications all wired through RevenueCat.
- Ads are served with Google AdMob (interstitial every 10 clears, optional rewarded ads for hints, coin doubling and extra restarts).
Challenges we ran into
- Making "rewind creates a wall" readable at a glance. Shadows needed their own neon language (dashed purple glass) so players instantly see what they can stop against.
- Guaranteeing fairness: every level had to be provably solvable and have a reachable three-star path, which is why the solver ships with the game.
- Localising puzzle text and tutorials into five languages, including right-sizing layouts for Japanese and Korean.
Accomplishments we're proud of
- 350 hand-tuned, solver-verified levels with a steady difficulty curve.
- A tile-by-tile level assembly animation that turns every level start into a small reveal.
- Shipping iPhone, iPad and an Android build in the same window.
What we learned
Monetisation works best when it stays out of the puzzle. Nothing you can buy makes a level easier except optional hints, which you can also get for free by watching an ad.
What's next for Rewind Courier
More chapters built on new shadow mechanics, a daily puzzle, and the Android release on Google Play.
Best Game Award
Gameplay. One rule (slide until you hit something) plus one twist (rewind leaves your past path behind as a wall). Each chapter layers a new interaction on top: buttons held by shadows, multiple shadows, door timing, cargo detours, paradoxes and portals. Levels are short, readable and always solvable, so the challenge is pure reasoning.
Art direction. Minimal isometric neon on a deep navy field. Walls glow orange, shadows are dashed purple glass, parcels are green. Every level assembles itself floor-first, then walls, props and the courier, so the first second of a level already teaches its layout. Couriers are collectible cube characters (animals, weather, celestial and mineral themes) rendered as six-faced sprites.
Monetisation fit. Puzzle players hate paywalls in the middle of thinking. Everything is earnable by playing. Revenue comes from light interstitials between levels, optional rewarded ads for hints and bonus coins, a one-time Remove Ads purchase (which also unlocks unlimited hints and doubled coins), and optional coin packs for cosmetic draws. All purchases run through RevenueCat. Nothing is pay-to-win.
Design Award
- Tile-by-tile level assembly: floor tiles fade in near-to-far, then walls rise, props drop, the courier lands last, all driven by a per-element timing window.
- Shadow walls as dashed neon glass that stack visually when shadows overlap.
- Level-clear panel with three hex badges that light up for Delivered, On Time and Full Cargo.
- Draw reveal: a three-phase "compression" animation that bursts into the rarity colour, with the whole room re-tinting to match.
- Native iPad layout that scales the entire interface proportionally instead of stretching a phone layout.
Try it
Free on the App Store: https://apps.apple.com/app/id6809398354 . Every level is playable without paying.
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