Every app is an island and that's just the way Apple wants it
Every app is an island. The iOS home screen's grid layout makes this clear – this app goes over here, that app goes over there, and goddamn if they're ever going to overlap. Developers have created workarounds to circumvent this restriction, but they're often clunky, imperfect, and inherently limited.
A lot of this probably has to do with iOS limiting itself to just one application at a time. Using iOS is like playing peek-a-boo with the world's most obstinate child. Both parties know that there are other apps behind that screen, but iOS is only willing to admit this after users have gone through the proper motions, poking and prodding and swiping until iOS is ready to remove its hands.
This is fine for simple tasks, but most actions use more than one app or service to get the job done. Consider email: Being able to cycle through an inbox on the go is great, but what if one wants to add an email to their to-do list? (Email is, after all, a to-do list written by other people.) If you want to make this happen on iOS you'll likely need to close the email app, open the to-do app, and handle business from there. Doing this once is irritating enough – having to do it over and over again feels foolish.
Or maybe someone wants to save an article to the read-later service of their choice. Because iOS doesn't offer universal access to other apps, it's up to developers to work with these read-later services and allow users to save articles for later consumption.
Some intrepid developers have found ways of bypassing this workflow. OmniFocus, for example, allows users to email a designated address and have an item added to their task list, and many read-later services can access a user's clipboard, detect a link, and asks if the corresponding page should be saved. Both solutions are patchwork fixes, the software equivalent to leaving a note at a drop-off point or stringing tin cans together. It only takes one error to interrupt the process and further waste users' time.
So far as problems go this probably falls somewhere between "I hate swiping through the app-switcher to find an app I used last week" and "Ugh, why won't Apple let me designate default apps?" Which is to say that it goes unnoticed for a long time before it finally bursts into users' consciousness and inspires a parade of expletives directed at the appropriate iDevice.
Apple could have fixed this with iOS 6, and, surprisingly, came about this close to doing so with its new share sheets. One button press offers a variety of actions, including the ability to share an item to Facebook or Twitter, add it to the Home Screen, or print it (which I'm sure is the most-pressed action) via AirPrint. How hard would it have been to allow developers to add their own apps to the list, turning most multi-step processes into two simple taps?
For now, users and developers have to work around Apple's restrictions, watching as it makes special exceptions for its partners (Twitter, Facebook) and its own actions (Print, Add to Reading List) and thumbs its nose at the little guys. The new share sheets prove that Apple can bridge the gap between the apps – it simply doesn't want to.
[Illustration by Hallie Bateman]