SourceForge - The Complete Open-Source and Business Software Platform.
Parse - Build applications faster with object and file storage, user authentication, push notifications, dashboard and more out of the box.
openDesktop.org - The website openDesktop.
AWS Amplify - JavaScript library for app development using cloud services
OSOR - OSOR is the Open Source Observatory, a project to provide a framework for developing and executing autonomous observations.
AWS Mobile Services - Storage, Analytics, Push Notif. & SMS Delivery SDKs