As iOS 5.1 beta is being seeded to developers, everyone has already carefully picked through it in order to find the tiny hints that signal upcoming Apple devices. And iOS 5.1 beta is full of those indicators – the most important of which (or at least the one destined to generate the most chatter) involves the next generation iPhone.

It appears that Apple has internally labelled the upcoming iPhone as iPhone 5,1. As 9to5Mac points out, an indication of a new 4,X model would probably suggest small changes, but nothing really new when it comes to the guts. A move from 4,1 to 5,1 could mean that the new iPhone will sport a shiny new A6 processor, one that has already been rumored for the device.

Other changes that have been rumored for the device, which we now see as the iPhone 5,1, have dealt with the external features – most notably that the new device will have a 4-inch display.

It was hinted by Apple sources earlier this month that the teardrop-shaped, aluminum backed iPhone 5 was in fact already prototyped, and it was scrapped as it approached launch. According to that rumor, the radically redesigned iPhone 5 was Steve Jobs’ baby, and he nixed it because he was unhappy with the bigger screen, which he thought “fragmented iPhones.”

According to the iOS 5.1 beta information, the next-gen iPhone is at least on Apple’s slate of upcoming launches. Could it be this phone that so many people wanted when Apple released the 4S?

The iOS 5.1 beta also outed the iPad 2,4, which is most likely not a reference to the iPad 3 but possibly the Sprint version of the iPad 2.

What do you think the next generation iPhone will look like – both inside and out? Let us know in the comments.