Customer.io

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.