They should also ban reviews from jailbroken devices, where users may have installed custom fonts or other "features" for which you can't possibly test and account.
And yes -- any test Apple does for this could be defeated, but I expect most jailbreak developers would side with their app writing comrades and let it stand.
And yes -- any test Apple does for this could be defeated, but I expect most jailbreak developers would side with their app writing comrades and let it stand.