Realtime messaging service. Free for up to 20 simultaneous connections and 100,000 events/day

Communication infrastructure in 5 minutes. Free tier includes: 100 SMS and calls, 3000 Emails, Push, Slack, MS Teams, WhatsApp, and more.

Realtime messaging service with presence, persistence and guaranteed delivery. The free plan includes 3m messages per month, 100 peak connections, and 100 peak channels.

Realtime messaging service, Pusher-compatible. Dev tier is limited to local development only and free with 100 concurrent connections, 1,000,000 broadcasts/month, unlimited client events, 32kb message size. ⬆️ Back to Top

Web Push Notifications - Free for upto 10k subscribers, unlimited push notifications, in-browser messaging

NATS.io as a service. Global, AWS, GCP, and Azure. Free forever with 4k msg size, 50 active connections, and 5GB of data per month.

SuprSend is a notification infrastructure that streamlines your product notifications with an API-first approach. Create and deliver transactional, crons, and engagement notifications on multiple channels with a single notification API. In free plan you get 10,000 notifications per month, including

SMS Gateway for Android™ enables sending and receiving SMS messages through your devices using cloud routing. Completely free cloud service (with recommended notification for usage above 10,000 messages/day to maintain quality for all users).

Realtime messaging service. Free for up to 100 simultaneous connections and 200,000 messages/day

Swift, Kotlin, and React messaging at 1 million transactions each month. Transactions may contain multiple messages.

Send push notifications to your iOS and Android devices. Effortlessly integrate via API or Webhooks and maintain full control over your alerts. Free plan: 50 messages per day to 1 device and 1 application.

The open-source notification infrastructure for developers. Simple components and APIs for managing all communication channels in one place: Email, SMS, Direct, In-App and Push. The free plan includes 30,000 notifications/month with 90 days of retention.

Notifications infrastructure for developers. Send to multiple channels like in-app, email, SMS, Slack, and push with a single API call. The free plan includes 10,000 messages/mo.

Send and receive text messages using your Android phone as an SMS Gateway. Free to send and receive up to 200 messages per month.

Connect your MQTT devices to the Cloud Native IoT Messaging Broker. Free to connect up to 100 devices (no credit card required) forever.

Multi-channel notification infrastructure for developers with a prebuilt in-app inbox and no-code template editor. Free plan includes 10,000 messages/mo.

All-in-one Customer Engagement and Automation Tool (email, push, SMS, product tours, banners and more) for SaaS. Free for up to 1,000 active users per month.

Scalable and secure serverless MQTT broker you can get in seconds. 1M session minutes/month free forever (no credit card required).

Single API for push, in-app, email, chat, SMS, and other messaging channels with template management and other features. The free plan includes 10,000 messages/mo.

RabbitMQ as a Service. Little Lemur plan: max 1 million messages/month, max 20 concurrent connections, max 100 queues, max 10,000 queued messages, multiple nodes in different AZ's