Digital - A simulator for digital circuits.
GoodBarber - GoodBarber is a mobile app creation platform.
LTspice - LTspice® is a high performance SPICE simulation software, schematic capture and waveform viewer with enhancements and models for easing the simulation of analog circuits.
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!
BOOLR - Open-source digital logic simulator
Dropsource - Mobile development platform for building native iOS & Android apps