Beeceptor - Unblock yourself from API dependencies, and build & integrate with APIs fast. Beeceptor helps you build a mock Rest API in a few seconds.
vatlayer API - Free VAT Validation & EU VAT Rates API
MockServer - Easy mocking of any system you integrate with via HTTP or HTTPS.
VatStack - Simplify VAT & GST for your digital business.
Webhook.site - Instantly generate a free, unique URL and email address to test, inspect, and automate (with a visual workflow editor and scripts) incoming HTTP requests and emails.
TeamLogger - Simple, employee time-tracking software with automatic screenshots and activity level monitoring. $1 / User / Month.