This second alpha release of Hedera Services 0.26 implements HIP-376, allowing smart contract developers to use the familiar EIP-20 and EIP-721 "operator approval" with both fungible and non-fungible HTS tokens.
Approved operators can manage an owner's tokens on their behalf; this is necessary for many consignment use cases with third party brokers/wallets/auctioneers.
Any permissions granted in a contract through approve() or setApprovalForAll() have an equivalent HAPI cryptoApproveAllowance or cryptoDeleteAllowance expression---and this expression is externalized as a HAPI TransactionBody in the record stream. That is, the HIP-376 system contracts expose a subset of the native HAPI operations, only within the EVM.