Last we heard, iFixit were in the process of tearing down an iPhone 4 and exposing its delicate innards to the world. That's now finished, and we've got a whole list of parts that help make the Apple smartphone's hardware special. Top of the list for most will be the doubled RAM over the iPad - 512MB versus 256MB, as expected - but there's also an FM radio receiver and a Gorilla Glass fascia.
That makes the front panel of the iPhone 4 particularly resilient to scratches and impacts, such as your new phone falling out of a pocket or bag. Handy, too, since Apple have securely glued the Retina Display LCD to the glass and the digitizer, which means that if one breaks then you'll have to replace all three components, potentially an expensive endeavour.
Otherwise the internals are dominated by a huge, 1,420 mAh Li-Polymer battery though Apple has found space for an interesting little audio chamber intended to make voice calls and media playback sound more impressive. More images at iFixit.