Thanks to an Indian developer that is known by the @satishtony username, you will be able to customise your Samsung Galaxy theme any way you want. The XDA member released themeDIY, an application that makes it very simple to design your own theme.
If you like to do everything yourself and shape everything in order to match your personal taste, you will find this new app very useful. Right now themeDIY is only available for Samsung devices, and you must run Android Nougat or Android Marshmallow in order to be able to use the app. We do not know if other devices will become available in the future.
Create your own Samsung theme
Coming up with a brand new theme for your phone is easier than it sounds. Thanks to this app all you have to do is to make some selections and the app will deliver a theme that will match your preferences.
The entire process is very simple. First of all you should think about the color scheme. There are over 1000+ pre-defined colors, simply pick one. These colors are for system apps and you can choose the primary status bar color or an accent color.
Afterwards, you will need an overlay. Select one and the job is almost finished. Next name your new them and then select build. The app should do the rest for you. Make sure the theme store is enabled and install the theme. After you are done go and disable the theme center and the store.
Disable the theme
If you no longer want the theme you can disable it via the Theme controller application that is inbuilt with themeDIY. You should know that you are also able to archive the source file of a theme for designers and developers.