What are some alternatives?
When comparing Apphitect IM and PubNub, you can also consider the following products
SendBird - SendBird is messaging-as-a-service.
Firebase - Firebase is a cloud service designed to power real-time, collaborative applications for mobile and web.
Mirrorfly - A Complete Chat, Video & Audio Calling Solution
Pusher - Pusher is a hosted API for quickly, easily and securely adding scalable realtime functionality via WebSockets to web and mobile apps.
Contus Fly - Contus Fly, an instant messaging solution for real-time mobile chat app development. Build 100% customizable mobile chat . be reachable at any given time.
Socket.io - Realtime application framework (Node.JS server)