Trelby
There are many reasons Trelby should be the first choice for screenwriters. First of all, it is an entirely free application that serves as an open-source platform. That means there are no fees, no extra charges for premium services, and so on. This is excellent news, given that most other reputable programs demand payment from you at some points.
Secondly, Trelby's cross-platform is interoperable with other screenwriting applications. For example, you can transport a Final Draft file into the Trelby system. Even better, it also lets you save your work in different file formats. Such features are rarely seen in other programs - even premium ones. The program is compatible with Microsoft Windows and Linux, too.
What is even more amazing is that Trelby never obstructs your workflow - on the contrary, it seamlessly integrates into your working process. Thanks to the rather limited number of buttons, the interface is basic and simple to use. Such designs are beneficial, especially if you wish to maintain your level of concentration while working.
Ratings: 4.2 stars (from 15 reviews)
Price: Free
Get started here: https://www.trelby.org/