WinStars is shareware. This means that you may use it freely. However, certain functions (As the access to the entire Gaia DR2 catalogue, the high resolution textures, the DSS function and the supplementary modules) are temporarily disabled.
If you wish to use the complete version of the software, you should purchase a user’s licence (this license is valid for the Window version). A full version of WinStars is also available on Google Play and on the Apple Store. The full version of WinStars 3 is free for Linux !
How to make payment (Windows version only) ?
A personal licence costs 6 €.
Use PayPal, a secure system of payment by email to receive your personal key immediately :
How to activate the complete version ?
After installation, select the “Buy WinStars 3” menu and enter your email and your personal code. More explanations are available here.