Appcelerator Titanium - Appcelerator Open Source
Bizness Apps - Create your own app or become a reseller and build apps for others
React Native - A framework for building native apps with React
Fuse - Fuse is a UX tool suite for mobile app designers and developers.
Onsen UI - HTML5 Hybrid Mobile App UI Framework - work with Angular, React, Vue, Meteor & pure JavaScript. Material & Flat design.
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!