As long as you are using Safari, and not a different browser like Chrome or Brave, you can install a browser extension on your phone like you would on your desktop to customize how your browser works. Personally, I use and recommend Homepage for Safari as a reputable and safe browser extension to use, but feel free to try out a different extension as well!
Once Homepage for Safari is installed in your browser, it is simple and straightforward to set the new tab page to your Feathermarks dashboard through setting the new tab url to https://feathermarks.com/home