We have started seeing this strange issue today. We have SPOnline SP hosted apps that have more than one client web parts. When we add multiple instances of these App parts (same app part or different ones) from same app to a page, they are all showing the same thing.
For example, we have a Report App with 2 web parts:
1. Single Report App part
2. Report Centre App part
On a page we have two instances of first App part and one instance of second app part. All these app parts are today showing the same data. There is no change in App and it was installed on site few months back. This has been working all along and only today we see this issue.
Thanks
Prakash Arya www.crowcanyon.com