Altium PCB Designer - Altium offers a top-notch, best-in-class PCB Designer to give engineers the tools they need to interlink with each side involved in the electronic design process.
KiCad - A Cross Platform and Open Source Electronics Design Automation Suite
Ktechlab - KTechLab is an IDE for microcontrollers and electronics.
Fritzing - Fritzing is an open-source initiative to support designers, artists, researchers and hobbyists to...
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.
EasyEDA - EasyEDA - Web-based EDA suite; runs in browser.