Known as a deep thinker about books, Craig Mod asked on Twitter about how black text on white and white text on black in a PDG can be inverted. Well it seems to be that this can be carried out in a few ways, they are as follows:

Using the accessibility option that is built-in in iOS

There are various features that can be seen in the Accessibility view under the General menu. These are designed so that the iOS can become a lot more useful in comparison to the default setting could be captured. Invert colors is one of the options that could be used for a few visual impairment forms.

To invert the display colors, all you have to do is tap the switch. For those who want to use it all the time, the sis said to be really useful. While you are using this, the Night Mode schedule can be disabled.

Extract the text with a PDF reader

To extract the reproduction of a file that is created, PDFs are used and can be previewed. This can be specialized software, page layout program or word processor. These PDF’s are created so well which helps in ensuring that within a document there is a seperate flow for the text. There are also tools that can be used to read the text aloud.

The Adobe Acrobat Reader app which is free and official has the option of flipping into a Night Mode that is inverted as well as view the stream of the text on its own.

Third party apps

There are also a few Third Party apps that can be used on this front, these apps not just help in loading the PDF but also for text extraction and even reading the text if you need it and wan to make any kind of changes to the background.