Amazon Cognito - Amazon Cognito lets you add user sign-up, sign-in, and access control to your web and mobile apps quickly and easily. It scales to millions of users and supports sign-in with social identity providers and enterprise identity providers via SAML 2.0.
Fondu - Open source free ICO smart-contract builder
NoPass.me - Open-source identity verification
thirdweb - thirdweb is an ecosystem of SDKs, dev tools, and dashboards that help teams build and manage web3 apps. Deploy custom or pre-built contracts to ETH, MATIC, AVAX, & more.
0xcert - Your ID, degree or house. 0xcert-ified on the blockchain
PAID Network - PAID network's SMART agreements will transform business