I have found a work around of sorts. I accessed gmail in the browser and then I bookmarked it (with login info saved). While, even there, the zoom also seems to be disabled... the font size is appreciably larger than when using the gmail app. Be sure you have the font in browser set to "huge" (browser/menu/more/settings/text size/huge) . Now I check my mail simply by launching browser/ menu button/bookmarks/gmail. It is very readable. In the gmail app font size was so small I actually needed a magnifying glass to read it.
Now my email is very readable and the pop up delete and archive buttons are very functional as well.