Samsung couldn't bother beefing up the mini and started from scratch. The Galaxy Alpha put metal back in Samsung's lineup, shaving off some thickness and weight along the way. It all worked out just fine and the new design was shared by the almighty Galaxy Note 4.
Apple took pride in having the best small phone for years but even Cupertino had to admit 4 inches just wasn't enough. The Apple iPhone 6 is the golden mean between the old 4" design and Apple's first phablet, the 5.5" iPhone 6 Plus. The aluminum unibody get even more refined.