Identity as a service. Alternative to state ID. Identity uniqueness is represented by it's forgery price.
Upala provides human uniqueness score to DApps. User account score is measured in dollars and represents the price of forgery - an amount of money (efforts) needed to forge the account. The score also shows how much a user values their account, because anyone at any time can delete their account and get the money corresponding to their score. The score could be used by DApps as a very reliable threshold to safely interact with a user.
Upala uses Merkle trees to store user score in a very compact way. Group owners (score providers) may update thousands of user scores instantly and with little gas costs.
Upala is cross-chain by design. Identical Upala protocol contracts are published on multiple networks (Ethereum, Matic, Near, etc.). Upala instances on different blockchains treat each other as native Upala groups wrapped over an outside identity system.
Demo is on Rinkeby and Mumbai