Yes - I’m using the bootstrap4 - the AppStudio included libraries for DataTables and BootSwatch
I found a couple of things researching this.
#1 - THIS IS NOT AN IOS ISSUE 
It is common to all devices.
#2 - This is not really a datatables issue, but the problem is in datatables when used with certain “dark” Bootswatch themes - eg, the actual data portion of the control is NOT totally theme compatible. And it’s not a Bootswatch issue. It would have been nice if Bootswatch and DataTables had ever talked to each other.
#3 - Try the datatables sample and change the theme to Cyborg. Since the sample defaults to striped data area, you can see every other line of data. I’m going to change some of the colors in my datatables using the same method used in the sample for highlighting to solve the problem.
#4 - The reference by @ghenne post to the styling is quite useful.
#5 - I was also trying to get a conformation from Thomas at BootSwatch that the method of changing themes on the fly used in this post: New App Design Considerations - Part 8 BS4 Themes Sample Project was the appropriate method. He has been radio silent for some time. As far as I can tell, the method works fine.