Ctrl+Space: Meet the Winners and Finalists of the Expo x ReactVision Hackathon

Ctrl+Space is a wrap. For one week, from 3 to 11 October, developers around the world built AR and VR apps in React Native with ViroReact, Expo and ReactVision Studio. No Unity, no new engine, just one codebase running on real devices.

We ran it with the team at Expo, and the brief was simple: build something real, record it running on a phone or headset, and tell us why it matters. Builders could pick the code track (ViroReact and Expo, with the ViroReact MCP server plugged into their coding agent) or the no-code track (ReactVision Studio and StudioGo).

Judges from ReactVision, Expo, Meta and the React Native community picked six finalists, who went head to head at the virtual finals on 15 October. Here is who won, and what they built.

Every project now has its own page with the demo video, the code and the judges' comments on the new Ctrl+Space project gallery.

1st Place and Best Geospatial AR: Amakin: City Game

Built by Reda Beggari (Morocco)

An AI named ITRI is rewriting the city of Rabat, and wherever it does, a portal opens. Players walk to the real monument, step through a ViroPortal into a 360° version of the place that has been drained of colour, and bring it back to life with hands-on puzzles. At the Oudayas, you crank a water pump until the fountain runs, then throw a canister of mist to reveal a key that can only be read from one spot. A daily portal adds a one-minute ritual and a streak.

Amakin took both the grand prize and the Best Geospatial AR award. It is built on Expo SDK 57 and ViroReact, using plane anchors, ViroPortal, a 360° ViroSphere with a custom shader, GLB models, particle mist and light estimation, with expo-location and react-native-maps for the city layer and a PostgreSQL backend for daily series and leaderboards.

"One of the most complete uses of Portals I've seen someone share... the overall app felt very polished and near releasable."

See the project · Watch the demo · View the code

2nd Place: Neo Rock 'Em Sock 'Em Robots

Built by David Grimsley (USA)

A modern take on the childhood classic, rebuilt as a tabletop AR fighter. You place the arena on a real table and battle a friend, either on the same table or long-distance, complete with sound effects, voice lines and a very silly uppercut reaction.

What impressed the judges was the multiplayer. Same-table play uses a hosted ReactVision cloud anchor and ViroSharedFrame to put both phones in one shared space (the co-location features that landed in ViroReact 3.0.0), and a relay handles long-distance matches. Expo Camera powers QR invites.

"A really good use of co-location... same-table co-location is properly done too, with a hosted cloud anchor and ViroSharedFrame putting both phones in that one space."

See the project · Watch the demo · View the code · Try it on TestFlight

3rd Place: Northbridge Space

Built by Dylan Ler (USA)

Household reminders are scattered across chats, whiteboards and calendars, but a reminder only helps where you can act on it. Northbridge Space lets housemates pin tasks to the dryer, the front door or the fridge in a 3D and AR scene. Each note has an owner, a due time and a 3D position, and a walk-through mode shows each person only their own open notes, room by room.

Northbridge Space runs in the browser on the ViroReact web renderer, so you can try it right now without installing anything.

"The camera flights between rooms feel smooth, and your video tells the story clearly."

See the project · Try it in your browser · Watch the demo · View the code

Best No-Code (Studio): Football Game

Built by David Grimsley (USA)

A tabletop AR football game built entirely in ReactVision Studio, with the built-in assistant guiding much of the setup and StudioGo for testing on device. It is a good reminder of how far you can get in AR without writing a line of code.

"Tabletop AR game use case seems fun."

See the project · Watch the demo · Open the Studio scene

The rest of the finalists

Medimagen

Built by David Grimsley (USA)

Medical scans are 2D, but our bodies are not. Medimagen puts 3D anatomy meshes, textured MRI and CT slices and transparent slice stacks into AR, so medical students, doctors and curious patients can place, scale and crop them on a table. Assets were prepared with 3D Slicer, Python, NumPy and VTK, and there is even some experimental GLSL volume rendering in there.

"Nice use of AR for exploring medical scans and anatomy. The interactions are well thought out."

See the project · Watch the demo · View the code

Guess the Qubit

Built by David Grimsley (USA)

Most Bloch sphere explainers are flat diagrams. Guess the Qubit puts the sphere in AR so you can walk around it, inspect the axes and state vector, and watch the Ry gate and measurement collapse, running on real simulator and IBM Quantum jobs. It is an AR port of David's earlier Unreal Engine game, rebuilt in React Native with ViroReact.

"A fun novel game... with some polish could be a fun game to play casually."

See the project · Watch the demo · View the code

What we took away

A few things stood out to us across the entries.

Real-world AR is where builders went first. Portals anchored to monuments, robots fighting on a shared table, notes pinned to the fridge. The strongest projects used AR to make a real place or a real object more useful or more fun, not to replace it.

Multiplayer and geospatial are no longer the hard part. Cloud anchors, co-location and location-based content showed up in finalist projects built in a week, by solo developers. That is exactly what we want the ReactVision Platform to make possible.

One person can ship a lot. David Grimsley made the final with four separate projects across both tracks, from robot boxing to quantum computing to a no-code football game. A single React Native codebase, a good coding agent and a week is enough to go a long way.

Thank you

A huge thank you to everyone who built, joined a workshop, asked a question in Discord or tuned in to the finals, to our judges, and to the team at Expo for running Ctrl+Space with us. Congratulations to Reda, David and Dylan, and to every finalist.

Ctrl+Space continues in person in London and Bengaluru, and you can find those on our events page. If the projects above have given you ideas, the ViroReact Starter Kit gets an Expo AR app running on your phone in minutes, and the team is in our Discord every day.