touchgrass is a gamified running app that turns real-world movement into a new form of data mining.
Built for ETHGlobal, it uses Yellow Network state channels, Reclaim Protocol zkTLS proofs, and Lighthouse Datacoins to reward users for verified, privacy-preserving real-world data contributions.
When users go for a run and hit START, touchgrass opens a state channel via Yellow Network (Nitrolite) between their wallet and the backend server.
As they move, their GPS coordinates stream off-chain in real time, allowing instant location updates and gameplay interactions with no gas fees.
While running, users can complete data quests — e.g., spotting potholes, EV chargers, or water fountains.
Each quest generates:
- a zkTLS proof (via Reclaim Protocol) verifying time & location without revealing sensitive data,
- an LLM-based validation step to check the photo content,
- and a Datacoin mint using the Lighthouse SDK.
When the runner presses STOP, the Yellow state channel settles on-chain — finalizing captures, verifying proofs, and distributing Datacoins to the user’s wallet.
All mined Datacoins are stored through Lighthouse and published to 1MB.io as consumer data assets.
We wanted to make touching grass productive — to turn outdoor activity into a decentralized data collection network.
Instead of mining blocks, users mine reality — contributing verifiable, privacy-preserving data that can power open maps, smart cities, and environmental analytics.
- Next.js — Web app frontend and dashboard
- Mapbox GL JS — Live map of runners, datacoins, and territories
- Yellow SDK + Nitrolite Protocol — Session-based off-chain transactions and on-chain settlement
- Reclaim Protocol (zkTLS) — Privacy-preserving proofs of time and location
- Lighthouse SDK — Datacoin minting and decentralized storage
- MongoDB — Run, user, and datacoin persistence
- LLM Validator (Python microservice) — Content validation for data submissions
Architecture: