Download PICSimLab - Prog. IC Simulator Lab. for free. PICSimLab is a realtime emulator for PIC, Arduino, STM32, ESP32, ... PICSimLab is a realtime emulator of development boards with MPLABX/avr-gdb debugger integration. PICSimLab supports microcontrollers from picsim, simavr, uCsim, qemu-stm32, qemu-esp32, and gpsim.

Proteus Design Suite by Labcenter Electronics, leading EDA software including schematic capture, advanced simulation, PCB autorouting, MCAD integration and much more.

Powerful online circuit simulator and schematic editor. Easy to learn.

multi platform circuit layout and schematic drawing tool - GitHub - bancika/diy-layout-creator: multi platform circuit layout and schematic drawing tool

Fritzing - electronics made easy

Horizon is a free EDA package enabling users to maintain a pool of electronic parts, draw schematics and design PCB-layouts