Push notification apps

Customer.io unifies data, messaging, and AI into one platform so every customer interaction gets smarter over time. Teams use it to build personalized campaigns across email, SMS, push, in-app, and more—using first-party data to reach the right people at the right moment. AI is built in to remove the grunt work and sharpen results, so marketers can focus on strategy. Trusted by 9,000+ brands including Notion, Lovable, Wispr Flow, and Cursor.

OneSignal is the market-leading customer messaging and engagement solution, offering mobile and web push notifications, in-app messaging, SMS, and email. Our powerful omnichannel platform enables 1M+ businesses to deliver over 10B+ messages daily. Powered by superior architecture, OneSignal is designed to scale with your business and deliver messages more quickly and reliably than the competition.