Pragma - The home base for Ethereum developers.
Airtable - Airtable works like a spreadsheet but gives you the power of a database to organize anything. Sign up for free.
Telnyx SMS API - Build global text messaging right in your app
StatusGator - Monitor all your hosted applications, vendors, and websites, and keep your team informed of outages. StatusGator is the world's premier status aggregator, status page, and website monitoring tool.
Notif.me SDK - A Node.js lib to send all your transactional notifications
WrapAPI - Build an API on top of any website