Android - Samsung 'Themes' - How to design/use my own Theme (for personal use)?

Question

In recent years, Samsung smartphones have included a Themes app.
There are plenty of Designers who publish Themes on there, for use on newer Samsung phones.
(Some are Free, others aren't)..

However, I would like to design my own Theme, purely for personal use.
In other words, I do not need it to go on the official Themes app.
(Again, purely for personal use).

Is there an Application (for PC), which I can use to Design my own Themes, such as these?
Any information about this topic is greatly appreciated!

Thanks.

Answer 1

ANSWER:
What I was after is called "Samsung Mobile Theme Editor".
More information can be found here this link, which is the official Samsung page for it.