The most expensive mobile phone currently available on the market is the Caviar iPhone 13 Pro Max "Discovery Solarius" edition, which is priced at $6.8 million USD. This phone is a custom-made version of the iPhone 13 Pro Max, featuring a back panel made of solid gold with 7.1 carats of diamonds and a rare piece of a meteorite called the Solarius rock. The phone is also decorated with engravings, including the Apple logo and a depiction of the solar system.
It is important to note that such phones are not mass-market products and are primarily targeted at ultra-high-net-worth individuals who are interested in luxury goods and are willing to pay a premium for exclusivity and rarity. Most people opt for more reasonably priced smartphones that offer high-end features and performance at a more affordable price point.