OneSignal Push Notification Platform

OneSignal is a customer engagement platform that enables businesses to send push notifications, in-app messages, SMS, and email through a single unified API. Founded in 2014 by George Deglin and Long Vo in San Mateo, California, the platform serves over 2 million businesses and developers worldwide, delivering over 12 billion messages daily. OneSignal supports web push notifications for Chrome, Firefox, Safari, and Edge; mobile push for iOS via APNs and Android via FCM; in-app messaging with rich media support; SMS through global carrier networks; and email campaigns with deliverability tracking. The platform provides powerful segmentation capabilities based on user attributes, behaviors, sessions, location, and device data, enabling highly targeted messaging campaigns. A/B testing, message scheduling, intelligent delivery (sending at optimal times per user), and impact tracking with conversion events help optimize engagement strategies. The REST API and SDKs for over 15 platforms including iOS, Android, React Native, Flutter, Unity, Cordova, and web enable seamless integration. The Outcomes product tracks how messages drive business results through funnel analysis and ROI measurement. OneSignal offers a free tier supporting unlimited devices with core features, with paid plans starting at 9 dollars per month adding advanced segmentation, A/B testing, and dedicated support.