iOS 7 continues Apple’s long history of gesture-based controls, some system-wide like the new swipe up from the bottom bezel to open Control Center, and some app (or multi-app) specific, like the new swipe right from the left bezel to travel back up the hierarchy Mail or Messages or the history in Safari, or the new toss to close apps in multitasking or tabs in Safari. There are also fantastic new “peek” gestures that let you pull left just a little bit to see individual time stamps in Messages, or pull down to turn a notification banner into the full-fledged Notification Center. Gesture controls can be tricky, however. If not direct they can be hard to discover, if not consistent they can be hard to habituate, and if not carefully considered they can collide and conflict with each other, both system-wide and app specific.
For example, when Apple first introduced four-finger navigation gestures for the iPad, you could accidentally swipe your way out of Fruit Ninja and into Mail. Now, you can swipe up in Hue to try and manage your lights and end up with Control Center instead. You can disable Control Center from being accessible inside apps, but since not everyone will, developers have to assume it’ll stay on, and cede basic gestures to Apple and the system.
Because the swipe-right gesture appears limited to certain apps, namely Mail and Messages, it won’t collide with other apps already using that gesture. However, the way Apple is implementing the interface in iOS 7 in general, because of that gesture in Mail or Messages, could make other apps look odd. Especially ones that currently use the popular “hamburger button and basement sidebar” design (I’m looking at you Facebook, Google apps, etc.) Even if iOS doesn’t stomp all over them, if they look wrong, or simply feel wrong on iOS 7, they may be forced to change and become more Mail or Messages-like. (And that might not be a bad thing.)
The good news is that all of these are direct manipulations. The bad news is that they’re not all consistent or symmetrical. Direct manipulations are more easily discovered than abstract gesture controls (which iOS stays completely away from for everything but accessibility), but in order for them to be habituated they need to be consistent. Notification Center is the perfect example. Any time, from anywhere, you can swipe down and what happens is exactly what you expect to happen – it appears. Control Center is the same.
The sideways gestures are where iOS 7 starts running into problems. First, because they’re only implemented in specific apps, they require the user to remember which apps include them. Worse, because they’re implemented inconsistently and asymmetrically across apps, they require the user to remember what they do in each app. That’s a high cognitive burden.
For example, in Safari – and in Photos, Calendar, Weather, and other apps before it – swiping from left to right takes you backwards through the sequence, and swiping right to left takes you forward. That’s logical and symmetrical. Even Camera, where swiping changes modes, moves through the modes in sequence and remains consistent.
However, in Mail and Messages, swiping from left to right doesn’t take you back through the sequence of messages, but up in the message hierarchy. You swipe back from message to message list to – in mail alone – message list box. Where it gets more challenging is swiping from right to left, because not only doesn’t that take you forward through the sequence, it doesn’t take you deeper into the hierarchy either. What it does is switch from direct manipulation to quasi-abtract command, revealing a destructive action – delete. That’s not only asymmetrical (swiping different directions results in different behaviors), and inconsistent with other apps, it’s a massive contextual change.
Photos can have hierarchies with albums, Calendar days with months, so there’s some overlap, but Apple’s recognizing that hierarchies in Messages and Mail are far more important in real-world use cases than they are in other apps, and re-assigning the gesture. They’re also keeping it simple by not, for example, leaving a one finger swipe to move through sequences of messages and using a two-finger swipe to move back to the hierarchy. That’s understandable and, in a world filled with trade-offs, sensible.
Switching from direct manipulation to go back to abstract command to delete is less understandable and sensible, but more a reflection of a legacy control Apple’s been using since iOS 1 (iPhone OS 1.0).
Here are some examples, with the Mail gestures (back vs. delete) on the left, Safari gestures (back vs. forward) in the center, and downward swipe gesture on Home (Notification Center vs. Spotlight) on the right:
In a perfect world swiping from right to left from the edge would move you into whatever message your touching, while touching a message and holding would allow you to delete it, much like cards and tabs. Apple has used modal gestures before, for example an edit button that changes an upward movement from the general scroll gesture to a specific item re-arranging gesture. Likewise, swiping down from the bezel reveals Notification Center, but swiping down from the screen in Home reveals Spotlight search. It adds complexity but also functionality. Detect if the gesture started at or near the edge, and if so make it navigation. If not, if it started on the meaty part of an item in a list, make it editorial. It will require learning, but not much.
The most important thing is consistency. Unless and until a swipe takes you back in every app where there’s something to go back to, it’ll always be harder to remember and become habituated to. Unless and until a forward swipe does something in every app where there’s a backward swipe, and there’s something to forward to, likewise. Unless you can pull a pass up out of Passbook as easily as you can shove one down and back into the stack… You get the idea.
For gestures to succeed for the mainstream, they have to always be where they’re expected, and always do as expected. With iOS 7, we’re only part way there.
Source from: http://www.imore.com