The EPUB File Reader tool for readers.

With this tool, you can read epub file type on Windows OS.
As you know already, the epub file type is:
EPUB is an e-book file format that uses the ".epub" file extension. The term is short for electronic publication and is sometimes styled ePub. EPUB is supported by many e-readers, and compatible software is available for most smartphones, tablets, and computers. EPUB is a technical standard published by the International Digital Publishing Forum (IDPF). It became an official standard of the IDPF in September 2007, superseding the older Open eBook standard.[2] The Book Industry Study Group endorses EPUB 3 as the format of choice for packaging content and has stated that the global book publishing industry should rally around a single standard.[3], see Wikipedia.

About this tool, you can read and download it on the official website:
EPUB File Reader is a free EPUB files viewer, can help you to open and read ePub e-books and documents. The software interface consists of two parts, the left will show document chapter directory, the right is a browser to show document content. This software is easy to use very much, it is a freeware and completely free to use.

The SmartDraw best tool to build diagrams.

This tool named SmartDraw is the best tool to build diagrams.
At 9 JULY 2019, this tool has been updated with new features:

• Sub-Charts and Processes; 
• OneDrive for Business; 
• easier Organization with drag and drop files and folders into other folders right on the template dialog;
• edit the name of a file using the click in the upper right corner of your diagram;
• New Modern Themes;
• Floor Plans features like set angles between walls and lines and show distances of windows and doors from the corners of a space;
• You can license your entire organization for one annual price;
• The SmartDraw Development Platform comes with Open API;
• and much more features;

This tool can use the online edition of SmartDraw on any computer or tablet or you can download it for the Windows operating system.
The online tool works well after I sign up with my mail.
The output can be export like Office, VSDX, VSD, PDF, SVG, and PNG file formats or can be share like link, mail or embed.
The output PNG file has filled with the trial copyright, but you can download an SVG file and use another editor to have a good output.
The price of this can start with from $9.95 (Per month, billed annually) or a one-time payment.
The Windows version stuck into Wize Installation Wizard window.
The official webpage can be found here.
Let's see a video tutorial from the official YouTube channel.