To store JSON data from your Rails app on a decentralized blockchain, you can use blockchain-as-a-service platforms like Moralis, Infura + IPFS, or Chainstack. These services offer easy APIs to store data on IPFS (for decentralized storage) and optionally link the content hash to blockchains like Ethereum or Polygon. Moralis is especially beginner-friendly and similar to Heroku in setup. Start by converting your Rails data to JSON, uploading it to IPFS via API, and storing the resulting hash on-chain.