[zwkrt]

I hate to jump on the bandwagon here, but imagine if Instagram released an update to their app to make it look like it did in iOS7. People would uninstall the app. They would be laughed at.

It isn't because current design trends are 'better', but they are exactly that, trends. If you don't keep up your app will look dated. To my unexperienced eye, the iOS7 design looks like the buttons take up way too much space; they are too visually interesting and distract from the content. But that isn't an objective take, it is just that I'm used to the current trend.

I could write about how Members-only jackets and moonboots were the hight of usability and design, but they were just a passing fashion. Nothing is really gained or lost, just changed.

[guilhermefront]

Perfect! Also imagine the UI designer suggesting something like iOS7 for their client, is simply not feasible.

I also think this is more about what is the current trend and this isn't exclusive to UI design. Clothes from the 1800-1900 also look cool, but no one is wearing because they're going to look weird to the eyes of everyone else.