In the HTML5test.com tests of HTML5 compatibility, the iPhone 5's Safari browser scores 360 points out of a possible 500, whereas the Galaxy S III's stock Android browser scores higher, at 380 points. Google's optional Chrome browser scores 369 points. Thus, for the first time since the InfoWorld Test Center began running these tests two years ago, Android browsers score higher than iOS's Safari.
The free Chrome browser is a bit more elegant than the stock Android browser, so I recommend you install it on a Galaxy S III. It also lets you sign in to your Google account, so all of your devices' Chrome bookmarks and state information are kept synced across the devices -- similar to what Apple's Safari 6 browser does in iOS, OS X, and Windows. But Chrome doesn't overcome the HTML5 and AJAX limits in Android.
Apple's iOS also integrates Twitter and Facebook in Safari and other messaging services, making it easy to participate in these common Web activities. Android is weak here, relying on the various social networking apps, which you must switch to to use.
Apple's iOS has long provided better business applications and better support of Microsoft Exchange servers than Google's Android has. But Google has been chipping away in this area in each Android update, and Samsung has gone beyond Google's own efforts by enhancing some of those apps in the Galaxy S III.
I prefer Apple's Mail app over Android's Email app because it's a little easier to navigate accounts and folders in Mail, and you can easily customize the accounts list, mark messages, and more easily move through messages. But the differences are minor. My only real beef with Android is the separation of Gmail from the other email accounts; Gmail email is accessed in a separate app than the rest.
Samsung's custom version of the Android Calendar app has a nice pullout feature to switch among calendar views, freeing more screen space for your calendar but keeping it easy to change views. On the S III's larger screen, you get more detail in the month view than on an iPhone. Plus, Samsung's calendar supports more types of repeating events than Apple's. In short, Samsung's calendar is better.
Samsung's custom Contacts app is also better than Apple's, thanks to its ability to add and edit groups -- and to let you send emails to all members of a group by using the group's name. Even in iOS 6, the iPhone still can't do any of those. Apple's Contacts app does let you assign more attributes to your contacts, but that doesn't make up for its backwardness about groups. Both the S III and iPhone 5 let you assign custom ringtones and vibration patterns for calls received from a specific person.
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