Apple Inc. (NASDAQ: AAPL) may have plans to release two new iPhone models this year, but so far we've seen convincing photos only of the highest-end one, the alleged iPhone 5S, to corroborate rumors about the next-gen smartphone. After MacRumors received a pair of photos of the alleged iPhone 5S's rear and inside specs, the Apple rumors site posted additional photos of the iPhone 5S that line up with previously leaked photos and further illustrate the differences between last year’s iPhone 5 and this year’s iPhone 5 successor in terms of specs and components.

The alleged prototype of the iPhone 5S on the left, and the iPhone 5 on the right. The iPhone 5S will feature improved specs in the processing and battery departments. Courtesy /

MacRumors’ photo depicts an iPhone 5S sitting next to an iPhone 5, and a quick glance reveals very few major changes to the inner specs. The iPhone 5S specs have been slightly modified in several ways to make room for new features – for example, the logic board features a slightly narrower profile to make more room for components and connectors, while the A6 chip has been replaced by a nameless Apple-built CPU, which, upon further investigation of its chip model number, looks to be a new A7 chip rather than a modification of the A6 chip currently featured in the iPhone 5. The Apple model number of the iPhone 5S chip is APL0698; the A6 chip in the iPhone 5 was model number APL0598, while the A6X chip featured in the fourth-generation iPad was model number APL5598.

The alleged CPU for the iPhone 5S. Apple will likely release an A7 chip inside the iPhone 5S, but chose to keep major identifiers to a minimum inside this iPhone 5S prototype. Courtesy /

Apple has a tradition of chip model number progression: The A5 chip, featured in the iPad 2 and iPad mini, debuted with an APL0498 model number, while a modified die shrink of the A5 changed the model number to APL2498. The tweaked A5 chip introduced earlier this year in the new Apple TV had a model number of APL7498. All of this evidence points to the legitimacy of the markings on the alleged chip inside the iPhone 5S, suggesting this chip has never been used before and is indeed an A7 chip. Further markings on the iPhone 5S CPU reveal 1 GB of Elpida DRAM.

Further inspection of the iPhone 5S chipsets reveals visible dates, which might correlate to when these chips were manufactured. For example, the iPhone 5S CPU features a date code of “1243,” which signifies the chip was made in the 43rd week of 2012, or simply late October. Another date code stamped on the DRAM -- 1239 -- suggests that portion of the chip was manufactured in September 2012. MacRumors believes Apple had an early prototype of the iPhone 5S in December 2012.

Apple features several identifiers in the alleged iPhone 5S that clearly show differences from the iPhone 5. The main iPhone 5S chip relates to its “K1A0062” stamp printed on the main chip, which is different from previous chips that started with an “N” rather than a “K” -- some, including the team at Chipworks, believe this may mean the chip is now being made by Taiwan-based chip foundry TSMC, not Samsung. This wouldn’t be surprising, since it was long rumored that Apple was trying to transition the manufacturing duties for future iPhone and iPad models away from rival Samsung.

More labels in the alleged iPhone 5S. Apple clearly has prototype placeholders for regulatory identifiers. Courtesy /

And as if it weren’t clear enough that the photos are showing an iPhone prototype, a close-up of the rear text on the alleged iPhone 5S shows labels of “X1234X” and “Model A1234,” which are clearly placeholders for Apple’s regulatory identifiers stamped on every iPhone.

The new camera in the iPhone 5S. We know Apple has added dual-LED flash, but we don't know if the camera specs have changed. Courtesy /

Besides the identifiers featured on the bottom of the phone, a close-up of the alleged iPhone 5S shows off some new specs we had seen in previously leaked photos. Even though we don't know if Apple has changed the specs of its 8-megapixel camera in the iPhone 5, Apple has definitely improved the flash on its rear-facing camera to a pill-shaped dual-LED flash, a departure from the circular flash in the iPhone 5. Another look inside the phone reveals a battery upgrade, from a 5.45Whr capacity in the iPhone 5 to a new capacity of 5.92 Whr in the iPhone 5S.

Apple iPhone 5S: Coming Off The Production Line For A September Release Date?

On Tuesday, GforGames released a photo originally posted on Sina Weibo of two alleged iPhone 5S units coming off an assembly line; the front face of the iPhone 5S looks identical to the iPhone 5, but the home button may feature a special hidden feature that’s rumored to be the centerpiece of the iPhone 5S – an integrated fingerprint sensor. With an ability to accurately and securely detect, encrypt and authenticate data about your fingertip, the iPhone 5S will likely eliminate the need for entering usernames and passwords again and again while using your phone. After Apple urgently acquired Florida-based AuthenTec last July, rumors of the integrated fingerprint sensor included in a future iPhone release started sweeping the Web. A fingerprint sensor makes a great deal of sense on the iPhone 5S: Since the iPhone has always had just one button, Apple knew this feature wouldn’t be complicated for users to locate or use, so the company invested millions of dollars into developing this technology alongside AuthenTec so competitors like HP, LG, Motorola, Nokia and Samsung couldn’t get their hands on it.

The alleged iPhone 5S coming off the production line in late June. Apple analysts expect the iPhone 5S to see its release date in September. Courtesy /

With iOS 7 set to release in the fall -- we believe September -- Apple will likely ship its latest mobile OS with a few new iOS devices; this is when we believe Apple will unveil and release the iPhone 5S. Specifically, we believe Apple will release iOS 7 on Wednesday, Sept. 18 – exactly 100 days after its unveiling at WWDC – and will then release the iPhone 5S on Friday, Sept. 20.

Another iPhone To Release Later This Year, Besides iPhone 5S?

Apple has traditionally released one new iPhone model each year, but 2013 looks to be the first year that breaks that tradition. In addition to the iPhone 5S, Apple will reportedly release its long-rumored “low-cost” iPhone, either called iPhone 6 or iPhone Light, later this year. For the iPhone 6, Apple is reportedly pursuing the same strategy it used for its newest, cheapest and thinnest iPod Touch, released in Mayv -- that is, to release a basic iPhone model with fewer ritzy features at a price point that’s easier to digest.

The iPhone 6, according to iLounge editor-in-chief Jeremy Horwitz, is a "cross between the iPhone 5, the fifth-generation iPod touch, and -- wait for it -- the iPod classic." With its 4-inch screen like the iPhone 5, a tapered bottom like the latest iPod touch and a rectangular shape like the iPod classic, the low-cost iPhone 6 is said to be substantially made from plastic but feature a hybrid chassis made of both plastic and metal. The right side of the iPhone 6 features a flat, centered SIM card tray like the iPhone 5, with the camera, microphone and rear flash located similarly to where they were on the latest-generation iPod touch.

This leaked photo shows off the alleged "low cost" iPhone 6, which features a plastic exterior that houses older-generation chipsets and specs. Courtesy /

But Apple's choice to release the iPhone 6 isn't about bold design; it's about an iPhone that's inexpensive to make and cheaper to sell. Apple will release the iPhone 6 globally, marketing it differently from its main iPhone line by allegedly releasing the iPhone 6 in a variety of candy colors (again like the iPod), but the company will reportedly focus on driving this phone into emerging markets such as India and China. Of the two developing markets, China is Apple's second-largest market, and Apple has many times tried to strike a deal with China Mobile Ltd. (NYSE:CHL), the largest telecommunications carrier in the world, with 703 million subscribers. If Apple is successful in selling the iPhone 6 on China Mobile, the iPhone 6 will be the first iPhone to release with TD-LTE frequency capabilities. Apple clearly wanted to close the deal early in 2013: On Jan. 10, Apple CEO Tim Cook visited China Mobile headquarters to meet with Chairman Xi Guohua to discuss “matters of cooperation.”

We expect Apple to release the iPhone 6 alongside the iPhone 5S in September to coincide with the main release date of iOS 7, but to release the two new iPhone models on separate dates to avoid heavy lines at its physical retail stores. For a preview of iOS 7, check out how to download and install the iOS 7 beta on your iPhone right now.

Apple sold 37.4 million iPhones in the quarter ended March 30, 2013.

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