The font problem is back with iOS 10.1.1
The October app update fixed the font problem in iOS 10 but the iOS 10.1.1 update brought the font problem back again. Please fix the app again. The support article listed in the app description doesnt fix the font problem. Turning off the default layout doesnt do anything to allow the font to go larger.
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OverDrive: eBooks & audiobooks, v3.5.8