Dropsource - Mobile development platform for building native iOS & Android apps
Public - Group chats.
Siberian CMS - Siberian is an Open-Source and Free App Maker. Unlimited Push Notifications. Unlimited features. Fully Customizable. Download it and build your own app now!
chitchat - Chat Room with Selfies and Pagers (yes, pagers!)
GoodBarber - GoodBarber is a mobile app creation platform.
Slack - A messaging app for teams who see through the Earth!