A core functionality of Candide Contracts is the Paymaster. The Paymaster is a contract and a Service that can sponsor transactions on behalf of users for many purposes.
Pay Gas in ERC-20
Generally, Ethereum transactions require ETH for paying transaction fees. With a Paymaster, users can pay transaction fees in several supported ERC20 tokens. This is realized via a transaction relay service (Paymaster) that accepts those tokens and submits the transactions to the blockchain, therefore paying the gas fee in ETH.
With the same functionality, users can submit transactions without paying any gas. CANDIDE, or other Dapps can pay transaction fees on behalf of a Candide Wallet via the Paymaster under certain conditions.