I’ve checked it here on my end and found out that there’s an on-going issue with QuickBooks Online when accessed through the updated iOS. I’ll refer you to another post in the Community, which will provide updates as they become available:
Current status (9/23/2016): Our engineers have determined […]
Resolution for 'another post issue: 'Quickbooks Online is not working on Safari 10.0.' available: Yes.
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