I agree with Lyle – the issue is likely to be related to an out-dated version of iOS.
The device is probably an iPad 2 (since the first iPad can’t run iOS 6), and that model can actually be updated to iOS 9 – though how well it will run is debatable. The latest version of Chrome on the App Store actually requires iOS 9, so the user is probably running an out of date version of that too.
I’d be curious to know if the login form shows in Safari – since the user will have that on their device by default.
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