OutSystems - Build Enterprise-Grade Apps Fast.
Bizness Apps - Create your own app or become a reseller and build apps for others
Kissflow - Kissflow is a workflow tool & business process workflow management software to automate your workflow process. Rated #1 cloud workflow software in Google Apps Marketplace.
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!
Mendix - Mendix is the fastest and easiest low-code platform used by businesses to create and continuously improve mobile and web apps at scale.
Dropsource - Mobile development platform for building native iOS & Android apps