Apple just unveiled the iPhone Duo, its first-ever foldable iPhone, at yesterday's "Surprise and Shine" event in Cupertino. It is the biggest change to the iPhone's form factor since the iPhone X in 2017. The book-style device opens to a 7.8-inch inner display, folds down to about a 5.5-inch outer screen, and starts at $1,999 for 256GB, with a 2TB configuration approaching $3,000. Pre-orders open October 16, and the phone ships October 23 in star white and night sky. The event was also historic for another reason: it was the first product keynote hosted by new Apple CEO John Ternus, who officially succeeded Tim Cook on September 1 after Cook's 15-year run at the top. Cook stayed on as executive chairman. Apple stock barely moved on the news, closing essentially flat around $316. Alongside the Duo, Apple also refreshed the iPhone 18 Pro and Pro Max, Apple Watch Series 12 and Ultra 4, and updated the AirPods Pro. The real question now is not whether the foldable looks impressive, it is w...