Mumble - Mumble is an open source, low-latency, high quality voice chat software primarily intended for use...
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.
Discord - Step up your game with a modern voice & text chat app. Crystal clear voice, multiple server and channel support, mobile apps, and more.
Truepush - Unleash limitless possibilities with Truepush and save up to $600 monthly. Free up to 10K Subscribers on all features.
GSC - With GSC, you can pick from any of 14 worldwide datacenters to host your own free voice server.
PushCrew - Push Notifications for Websites