Plex

the third in this list of best movie streaming sites, which lets you stream online for free and with great speed and quality. On this website, you can watch movies on tablets, smartphones, computers, and any other devices that allow streaming online.

With the free version of Plex Media Server, you can enjoy its essential utilities apart from streaming movies online. An example of such a utility is centralizing your downloaded media files and sharing them with your loved ones.

Pros:

It allows for use on all platforms such as Windows, iOS, gaming platforms and devices, Roku, Android, etc. It is very compatible across devices.
The free version is useful for basic functionalities.
It is user-friendly even for beginners.
Cons:

To enjoy the full features of the tool, you need to pay for the Plex Pass.
It is not as customizable as some of the best movie streaming sites online.