OneSignal - Customer engagement platform used by over 1 million developers and marketers; the fastest and most reliable way to send mobile and web push notifications, in-app messages, emails, and SMS.
Revue - The easiest way to create and send a curated newsletter
Truepush - Unleash limitless possibilities with Truepush and save up to $600 monthly. Free up to 10K Subscribers on all features.
Substack - Substack makes it simple for a writer to start an email newsletter that makes money from subscriptions.
PushCrew - Push Notifications for Websites
Postie - Email campaigns built for you using your best social content