New iPhone, new “world’s most expensive phone.” As the iPhone’s design changed slightly, Hughes’s had to change with it. The iPhone 4 took its screen to the edge, pushing out the favored home of smartphone diamonds. Ever the adaptive designer, Hughes moved the diamond collection to the sides and shoved a whole bunch more in there.
According to Stuart Hughes, The Diamond Rose had roughly three times as many diamonds as its predecessor, clocking in at approximately 500 in total. The back of the phone was made from rose gold, giving the Diamond Rose edition its name, and the Apple logo sparkled with its own diamond coating.
Once again, the home button was replaced by one large pink diamond. This time it was even larger, coming in at 7.4 carats, with the option to replace it with an 8-carat diamond. Just like before, it came delivered in a box of cut granite. Inside, the Diamond Rose boasted 32GB of internal storage, which sounds like a joke when compared with today’s smartphones but was the best the iPhone 4 had to offer.
Only two Diamond Rose phones were produced, and they sold for £5,000,000.00, or approximately $6.5 million.
Source: https://www.slashgear.com/840933/the-10-most-expensive-smartphones-in-the-world/