I am currently implementing some Powerview in excel that is used on sharepoint online. My problem is that I can't get excel web app to save automatically when something is changed in excel web app only when it is saved in the real client, what am I missing?
I tried your issue and unable to reproduce it. I use an Enterprise E3 license and on my team site I have checked the default behaviour in advanced settings:
To enable editing I need to switch from viewing to editing before start:
When this is done, it works like a charm. But I don't use Power View - which I'm afraid to say isn't supported:
You can only edit Power View sheets in Excel 2013 client.
Reference: Power View in Excel on Office 365 or in SharePoint Server