This prototype developed for the Building on Bitcoin Hackathon stores and shares your data off-chain using Gaia. Files are private and encrypted by default and can only be decrypted by connecting your wallet. You can also store public files, which will be stored in an unencrypted form.
You can then decide to share your private data, either with a role-based or token-based access mechanism using smart contracts on the Stacks Blockchain. The protoype runs on the Stacks testnet. You need to request test-STX from the faucet to pay for the transaction fees.