Arcamari Damacy is an Android app built with the ArcGIS Runtime SDK that encourages people to explore the world, inspired by the classic game Katamari Damacy.

Link to Slides

Team members:

  • Ed Carroll​
  • Indhu Kamala Kumar​
  • Nathan LaPré​
  • Matthew Nelson​
  • Denise Vachon (not shown on Devpost)​
  • David Vitale


The 2004 PlayStation 2 Namco game Katamari Damacy is a wild ride through a virtual 3D world. Your character rolls a large lump (Katamari) around, picking up objects as it rolls and increasing the Katamari's diameter. You only have so much time to pick up as many things as you can. We wanted to bring this game into the real world, using real-life features and the Runtime LocationDisplay API to track the user's current location. This could encourage people to get outdoors and see the world, similar to Pokemon Go.

What it does

When you launch the app, it loads a Web Map hosted on ArcGIS Online that contains layers describing the features that can be collected. Each layer has a feature table with a column defining the diameter of each item. The app tracks the user's location, replacing the default blue location dot with the Katamari image, which rotates periodically. When the user's location updates, the app calculates whether the player is currently close enough to the feature to roll it up. If it is, the feature is consumed and disappears from the map, and the Katamari grows larger by a fraction of the feature's diameter. Running counters track the number of feature types consumed. A timer tracks the amount of time left to collect items. When the timer runs out, all features disappear from the map, and the collected features re-appear on the map, allowing the user to check out the things they collected.

How we built it

  • The app is built with Android. Targets Android SDK version >=21.
  • The location is tracked with Runtime's LocationDisplay API.
  • We created the Web Map and its constituent feature layers in AGOL and consume it with the Runtime SDK.

Challenges we ran into

  • None of us had any significant Android app development experience.
  • Feature query limits on feature services...we didn't know that was a thing.
  • Our team is almost entirely developers, which made it trickier to wrangle data without formal GIS training.

Accomplishments that we're proud of

  • Making a working app that's fun to play in three days!

What we learned

  • How to make an Android app.
  • It was interesting to learn the experience of developers using the Runtime API.

What's next for Arcamari Damacy

In the future,

  • Migrating the app to a Scene view could provide an experience more true to the original Katamari game,
  • Making the app multiplayer could allow for a more competitive experience where you could collect other player’s Katamari if you were bigger than them and you would compete over resources to become bigger, and
  • A mechanism to dynamically load different feature layers could allow people to play the game all over the world (currently you will only find features in Redlands).

Built With

+ 3 more
Share this project: