None is a direct clone of Sky Tools, but for many visual observers, Stellarium + a logging app is more than enough.
To ensure the software functions accurately, you must configure your local environment:
The safest, most reliable, and most ethical path is always to support the developers by purchasing a legitimate license. This gives you peace of mind, access to all the incredible features of SkyTools 4, and the assurance that you are using the software exactly as intended, without any hidden risks.