iOS: While a keyboard certainly isn't always useful with your iPhone or iPad, keyboard shortcuts certainly are. MacStories has started a running list of all the new shortcuts for Safari, Mail, and Pages.
For the most part, all the text editing keyboard shortcuts have worked in iOS for a long time, but MacStories has collected a few of the new ones in iOS 7:
Safari
L to Open Location
T to open a new tab
W to close the current tab
R to refresh the current tab
. to stop loading the current tab
N to create a new message
⇧D to send a message (from the Compose screen, it also works in other apps that implement a Mail sharing feature)
Backspace key to delete the currently selected message
Up/down arrows to select suggested email address in To/CC/BCC popover fields
Pages
⇧K to comment
⌥K to show next comment
⌥⇧K to show previous comment
MacStories' list is still growing, so head over there for the always updating list of new keyboard shortcuts.
A List of New iOS 7 Keyboard Shortcuts | MacStories
Photo by bfishadow.