OneSignal

OneSignal is the customer engagement platform most used by developers for push notifications: the free plan already covers the vast majority of use cases, with unlimited mobile push and up to 10,000 web subscribers, with no payment needed to start.

OneSignal is a customer engagement platform that handles push notifications for mobile apps and websites, in-app messages, email and SMS from a single interface. You integrate OneSignal's SDK into your app or install the code on your site, and from that point you can send notifications to your users directly from the dashboard or via API. Segmentation features let you send messages to specific groups based on behaviors, attributes, geographic location or defined events. A/B testing is available to optimize messages, notification performance analytics, and the Journeys system for building multi-channel automated sequences. OneSignal supports iOS, Android, web (Chrome, Firefox, Safari), email and SMS, and integrates with major CRMs and analytics platforms. Built with strong developer focus, it has very comprehensive documentation and SDKs for all major frameworks — React Native, Flutter, Unity, Cordova, Xamarin. The free plan is among the most generous in the category for basic use cases: unlimited mobile push, up to 10,000 web subscribers and in-app messages.

For developers, product teams and marketers who want to send push notifications to mobile app and web users, with a free plan that covers most initial needs.

OneSignal's free plan includes unlimited mobile push, up to 10,000 web subscribers, in-app messages, 10,000 monthly emails and access to Journeys. The Growth plan starts at $19 per month (base, then scales with MAU and channels) and adds advanced segmentation, more data history, advanced A/B testing and priority support. Professional and Enterprise plans are custom-priced. Note: the $19 base cost is the starting point, but for significant volumes (100,000+ subscribers) the monthly cost rises quickly into hundreds of dollars.