Overview
OpenLitterMap is a free citizen-science app that lets anyone photograph a piece of litter, tag it, and add it to a public map of the world's litter and plastic pollution1. Each photo records where and when it was taken, and the contributor tags the object, its material, and the brand on the packaging2. After a check, uploads become open data that anyone can browse on the map1 or download3.
Founder Seán Lynch launched OpenLitterMap in April 2017 and set out the idea in a peer-reviewed paper describing how mappers earn Littercoin, a reward token first designed on Ethereum4. A Fund 4 grant from Project Catalyst, Cardano's community-voted funding programme, paid $50,000 for a plan to move Littercoin to Cardano and send it to contributors' Cardano wallets5. A Cardano version of the token was created on the main network and later burned, meaning permanently destroyed6, and the project's separate Ethereum Littercoin code is listed as in development7.
Key Features
- A live map of where litter turns up. Verified uploads appear as points on a global map, and visitors see live notifications as new photos arrive from around the world1.
- Brand-level detail on packaging. Contributors choose from more than 200 predefined tags or type their own words, so the data shows which companies' products end up on the ground2.
- Data anyone can take away. Verified observations become public open data1, and visitors can download the records for a chosen place as a CSV spreadsheet file3.
- Code anyone can reuse. The web platform's source code is public on GitHub under the GPL-3.0 open-source licence, so others can study, copy, or adapt it8.
- Research that builds on the data. OpenLitterMap began as academic work2, and the site keeps a public list of research papers that cite the project9.
What to Expect
The homepage walks through three steps: take a photo, tag what you see (including whether you picked it up), and share the maps or download the data10. From there you can open the global map to see what people have logged1, or compare countries by tags, photos and contributors on the Locations page11.
To contribute, you create a free account and upload geotagged photos through the iPhone app, the Android app, or the website. You can upload whenever you like, and each upload gets its own link that takes anyone straight to that spot on the map2. Contributors also climb public leaderboards2.
New contributors stay anonymous by default, and an administrator reviews their tagged photos before they appear on the public map. Once an account earns trusted status through consistent, high-quality contributions, its tagged uploads appear on the map without delay12.
Researchers and developers can follow the work in the open. The original Cardano smart contract code for Littercoin, the programs that set the token's rules on the blockchain, sits in an archived repository that its owner has set to read-only13.
