With Android, every relevant app from the browser to the photo gallery includes a share button. When you tap share, you're given an extensive and universal list of apps you can share with. And that list grows, depending on what software and services you have installed, from Facebook to your SMS messenger to Bluetooth transfers. So if, for example, you join Pinterest and install its app, you can share directly to that from any app with a search button.
Rather than providing you with one share list to rule them all, the iPhone 5 lets each app developer create his or her own share menu, which has a finite list of services that developer feels like supporting. The default Safari browser and iOS photo gallery apps can only share to Facebook, Twitter, Email and messaging. Google, Flickr, Pinterest, Google Talk, and any of 100 other services need not apply,