LTspice is described as 'IV is a high performance Spice III simulator, schematic capture and waveform viewer with enhancements and models for easing the simulation of switching regulators' and is a circuit simulator in the education & reference category. There are more than 25 alternatives to LTspice for a variety of platforms, including Windows, Linux, Mac, Web-based and Android apps. The best LTspice alternative is KiCad, which is both free and Open Source. Other great apps like LTspice are QUCS, Pspice, Circuit JS and Proteus PCB design.