Time location

Yeah, that sounds frustrating! Having the time hidden by your thumb can be a real issue, especially in fast games where every second counts.
It would be great if Chess.com allowed customizable UI options for things like clock placement. Maybe you could suggest it in the Site Feedback section? I bet a lot of mobile players would appreciate that change.
In the meantime, have you tried rotating your phone or adjusting how you hold it? Not a perfect solution, but it might help a little.
Hope they consider this tweak!