Apple - When watching Apple’s tutorial videos about iWork, each completed video gets a checkmark next to its name.
iOS 6 - Keyboard detects specifics of language and displays correct diacritics depending on the part of a word.
Apple - searching for colloquial or rumored product names (such as iTouch or iTablet) refers you to the appropriate products.
OS X - Finder prevents you from accidentally modifying the extension when renaming a file, but only for known file types.
Foursquare iOS app - if you drag your uploaded photo to the left, you see a hidden mascot holding a camera.
iTunes - Lets you filter song rating by typing asterisk symbols in search bar
Apple - The image used in the Apple Store for the MacBook Pro subtly shows the anti-glare option of the MacBook Pro with Retina Display.
/via Mario Uher