Long-story short: a developer created an app that takes a calculator widget onto iOS 8’s Notifications Center. The AppStore team approved that and even promoted the app on their first page.
A few weeks later the developer was asked to remove that functionality if he wants to keep his app in the AppStore. Note: they asked him to remove the Notifications Calculator, not all functionality.
As expected, most developers were shocked or amused by the decision. See this story.
The way I see it: when you visit someone’s house you play by their rules. If you don’t like it don’t come around. If they change the rules you still have to play by them. It’s their house and they have the right to do so.
I know it’s frustrating for a developer to have a rejection after his app was promoted by Apple and I think the company should have made it clear. On the other hand, the Notifications Center was not meant as a way to get shortcuts to apps, just notifications.
Hence the name. It’s not called “the widgets center” or “Dashboard”. Maybe Apple will include such functionality in iOS 9 or 10, but until then just have your app use that area for notifications. Or maybe Apple will reverse its policies for iOS 8.
Also, I would not use a Notification widget that takes more than half of that area. And if you really need a calculator handy you could just flip the Control Center upwards and tap on the calculator icon on the bottom row.
Update: less than 24 hours later Apple reversed their decision. Just as I was saying… :)