One of my favourite features of Windows Phone 8 is the way tiles on the home screens of devices can be resized to show more or less information. This allows a user to increase the size of an app's tile (or icon) like Mail, in order to see new email messages right on the home screen of the phone, rather than having to launch the app.
iOS doesn't support widgets. For the most part, I think that's a good thing; widgets on Android can very quickly make the entire UI extremely ugly. However Max Rudberg, a great designer, has come up with a cool concept for how icons on iOS could become resizable in order to show more information than just an icon and allow easy access of common tasks without having to launch the app.
There is certainly a risk with a concept like this: how quickly could a device become ugly? What would be the performance cost of doing this? Would iOS start to feel slower because these "mini-apps" are running?
There are difficult design challenges, too: app icons on iPhone aren't the same size as app icons on iPad. This means the "widget" sizes across devices wouldn't be equal. Non-equal widget sizes for iPhone and iPad leads to more work for app developers and designers. With widgets enabled, the iPhone might lose the sense of simplicity it is otherwise known for.
There are certainly compelling reasons for widgets like the ones shown in Max's video. Being able to quickly turn on and off alarms from the clock app would be extremely useful.
It may make sense for just Apple's own apps to have this feature at first — they would be tastefully designed and a great example for how other developers could use larger real estate on the home screen. Eventually, all apps could implement the feature — however it may well have a separate review process to ensure the implementation is not ugly or slow. This could solve the "ugly" problem. Perhaps the complexity problem would solve itself: only users who knew how to increase an app's icon would ever see these widgets. That would keep the iPhone looking simple and beautiful for most people, like it is today.
Perhaps this concept could be implemented, after all. I'm not holding my breath, though. So far, the biggest deviation from a grid of rounded rectangular icons on iOS is in Notification Centre. Perhaps we're more likely to see a feature like resizable UI elements there.