GeneXus - Web & Mobile application development platform
Bizness Apps - Create your own app or become a reseller and build apps for others
B4J - 100% free development tool for cross platform desktop and server apps.
GoodBarber - GoodBarber is a mobile app creation platform.
NotePlan - Make plans inside an individual markdown note for every day in your calendar. Use it as a journal for your daily tasks and plan todos in advance. For Mac, iPhone and iPad.
Fuse - Fuse is a UX tool suite for mobile app designers and developers.