FreeOffice: The function View side by side is not included in SoftMaker FreeOffice.
Android/iOS: This function is not available in the Android or iOS version.
The command View side by side 
allows you to display the contents of two documents side by side on the screen, while scrolling synchronously through both documents. This is useful if, for example, you want to compare a revised document with the original document.
Proceed as follows:
| 1. | First, open the two TextMaker documents that you want to compare. |
| Tip: It does not matter whether you open the two documents in different program windows or as document tabs in the same program window. |
| 2. | Choose the ribbon command View | group Side by side | View side by side . |
| Note: If more than two documents are currently open, TextMaker first asks which of them is to be used in the other window. |
The screen now displays the two documents side by side.
Scrolling synchronously through both documents
To make it easier to compare the two documents, the Synchronize scroll 
feature is automatically enabled after you choose the command View side by side. As a result, you can scroll through the two documents in parallel. Thus, if you scroll up or down in one of the documents, the other document follows synchronously.
If you want to cancel parallel scrolling, disable the Synchronized Scrolling feature by clicking on the button. The two documents will still be displayed side by side, but scrolling in the documents will now be independent of each other.
Moving and restoring window positions
If necessary, you can adjust the width and height of the two windows separately by dragging the edges of the respective document with the mouse.
Use the command Restore positions 
to rearrange the windows evenly next to each other on the screen.
Undoing "View side by side" again
If you want to undo the enabled View side by side feature, click on the button again. The side-by-side arrangement of the two windows will then be released, and they will be displayed on the screen in their original position and size.