Pusher Beams - Send push notifications programmatically at scale
Beeceptor - Unblock yourself from API dependencies, and build & integrate with APIs fast. Beeceptor helps you build a mock Rest API in a few seconds.
Truepush - Unleash limitless possibilities with Truepush and save up to $600 monthly. Free up to 10K Subscribers on all features.
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.
PushOwl - Re-engage website visitors with push notifications
MockServer - Easy mocking of any system you integrate with via HTTP or HTTPS.