On Tuesday, Apple Inc. (NASDAQ: AAPL) is poised to introduce two new iPhone models at its Sept. 10 media event, including its high-end iPhone 5 successor, the iPhone 5S, and the company's long-rumored budget iPhone. The latter could be called one of many names, but most rumors have favored the name iPhone 5C since this photo of the phone's plastic packaging surfaced on the Web last month.

The budget iPhone will certainly be an interesting announcement, since Apple has never introduced more than a single iPhone model at a time, but most of the crowd's attention will deservedly fall on the iPhone 5S, which is expected to release with the latest and greatest technologies from Cupertino, Calif. 

We've been following rumors of the iPhone 5S for more than a year now, and we believe we have a great picture of what users can expect from Apple's high-end iPhone release. Here are five features of the new iPhone 5S you should expect to see at Apple's big Sept. 10 event. 

1. Improved Battery Life

In late June, Apple rumors site MacRumors posted alleged photos of the iPhone 5S, which greatly detailed the differences between last year’s iPhone release and this year’s iPhone 5 successor, in terms of specs and components. The logic board within the alleged iPhone 5S is slightly narrower than the iPhone 5’s logic board, presumably to make room for new components and connectors, but we definitely noticed Apple gave its battery a slight, albeit important, upgrade. The 3.8-volt lithium-ion polymer battery in the iPhone 5S looks to have an upgraded capacity of 5.92 Whr, compared to the 5.45 Whr in the iPhone 5.

The battery in the iPhone 5, according to Apple, lasts up to eight hours on 3G and 10 hours on Wi-Fi, and can play 10 hours of video and 40 hours of audio. We don’t know to what extent the improved battery will extend the typical life of the iPhone 5S, but given how Apple worked so hard to implement energy-saving technologies in the new Mac software, the iPhone 5S -- with the help of iOS 7 -- may get an extra hour of battery life or two compared to last year's iPhone release.

2. A Faster A7 Processor

MacRumors’ photo depicts a nameless Apple-built CPU, which, upon further investigation of its chip model number, looks to be a completely new A7 chip rather than a simple modification of the A6 chip currently featured in the iPhone 5. The Apple model number listed on the iPhone 5S chip is APL0698; the A6 chip in the iPhone 5 was model number APL0598, and the A6X chip featured in the fourth-generation iPad was model number APL5598.

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. A modified die shrink of the A5 changed the model number to APL2498, and the tweaked A5 chip introduced earlier this year in the new Apple TV had a model number of APL7498. Several other signifiers listed on the iPhone 5S chipset show how the CPU was built in the 43rd week of 2012, or late October, while another stamp shows how the new chip was built by Taiwan-based chip foundry TSMC instead of Samsung. All of this evidence points to the legitimacy of the markings on the alleged CPU inside the iPhone 5S, suggesting this chip has never been used before and is indeed an A7 chip.

3. New Camera, Dual-LED Flash

Apple continually pushes the limits of its smartphone camera technology with each new iPhone release, and 2013 won't be any different. It may not seem like much at first, but Apple has clearly adjusted the size and shape of its rear camera LED for the iPhone 5S: The iPhone 5 features an 8-megapixel camera with a singular circular flash module, but many alleged photos of the iPhone 5S have indicated a new pill-shaped dual-LED flash. The new dual-flash camera features may provide better lighting and more accurate color saturation and brightness in photos, but Apple is also expected to release a newly upgraded camera system entirely; rumors point to 12 megapixels, but we may also see an enhanced element lens and aperture in the iPhone 5S.

4. Slow-Motion Video Photography

As tipped by 9to5Mac, iOS 7 contains code for a new feature called “Mogul,” which won’t activate on the iPhone 5 due to “unsupported hardware." This suggests the "Mogul" software is made specifically for a future iPhone. So in the same way Siri was exclusive to the iPhone 4S, the new Mogul feature looks to be one of the few exclusive features to the iPhone 5S.

But what does Mogul do exactly? According to “analysis and testing of the code,” 9to5Mac discovered that Mogul will allow the iPhone 5S to capture video at “an exceptionally fast and precise rate,” indicating a potential recording rate of 120 frames per second. With such a fast frame rate, it seems likely the iPhone 5S will support slow-motion video, since slow-motion effects require frames to be captured at a fast rate, which then appear slowed down when the video is replayed at a standard speed -- the Samsung Galaxy Camera can already do this. With a presumably enhanced camera – the iPhone hasn’t received a camera upgrade since the iPhone 4S – this additional Mogul feature should give the iPhone 5S the “cool factor” it desperately needs. Especially since there appears to be only one other “killer” feature in the iPhone 5S…

5. The Fingerprint Sensor

It's been widely presumed that the “S” in the “iPhone 5S” will stand for “security,” especially since Apple urgently acquired Florida-based AuthenTec last July. AuthenTec's most prized, noteworthy product, the "Smart Sensor," is likely what Apple was after.

At just 3mm high and 1.3mm thick, AuthenTec's first Smart Sensor, which was announced in May (right around the time Apple upped its efforts to buy the company) crams a 500 ppi, 192x8 pixel detection matrix and all the fingerprint matching technology necessary to accurately and securely detect and encrypt data about your finger. Furthermore, AuthenTec's "anti-spoofing technology" ensures that only real fingerprints are read by measuring the properties of your finger's skin and translating those unique traits into digital data that's then compared with the "expected [fingerprint] properties."

The fingerprint sensor may allow the iPhone 5S to automatically authenticate one’s identity, possibly negating the need to input personal data on one’s phone again and again, or even the need to remember a passcode combination. Patently Apple offers a fantastic description of how this biometric fingerprint technology in the iPhone 5S could enhance iPhone activities like e-commerce. But that's not all: AuthenTec's technology is so smart, it can differentiate your fingers so as to associate different functions with those fingers. For example, you can use different fingers to play music, or ask for directions, or call a particular contact.

One would think Apple plans to integrate AuthenTec’s Smart Sensor directly into the iPhone’s signature home button, but we highly doubt the full functions of the fingerprint sensor will be realized when the iPhone 5S sees its initial release date in a couple of weeks. For some time, it looked doubtful that Apple would actually be able to implement the fingerprint sensor at all, but given a handful of convincing photos of the iPhone 5S box and that noticeable ring around the home button (embedded below), we believe the fingerprint sensor will work, but will be limited in its early going (Siri, anyone?).


Bonus Feature: 3, Possibly 4 Color Options

Call it a feature, but adding more color options for the iPhone could be a determining factor for undecided mobile consumers. The iPhone 5 is available in just two color themes -- slate and silver -- but the iPhone 5S is said to release at least one more color option -- most notably, we've seen leaks and reports pointing to a gold or champagne iPhone 5S, which may or may not be exclusive to a 128 GB storage option. It makes sense for Apple to release an iPhone color exclusive to the phone's highest storage capacity, basically making the gold iPhone 5S feel like a more desirable luxury item rather than just a smartphone. But with rumors on another graphite color option, we're not completely convinced Apple will pursue such a strategy. We've embedded a video of the gold iPhone 5S below.

On top of slate, silver and gold, big-time Apple product leaker Sonny Dickson posted photos of a graphite iPhone 5S. Given Dickson's reliable background, we have no reason to not believe him, but we haven't seen nearly as much footage or coverage of this particular option, so we're not going to "bet on" this rumor quite yet.

Apple iPhone 5S Coming: When Will Its Release Date Arrive?

We originally predicted that Apple would reintroduce iOS 7 on Sept. 10 and release the operating system one week and one day later on Sept. 18. Given how Apple tends to release its newest iPhone two days after the release date of its newest iOS, we believed Apple would release the iPhone 5S on Sept. 20, and we still stand by that prediction.

Apple has reportedly restricted vacation time for Apple employees between Sept. 15 and 28, while T-Mobile has implemented vacation blackouts between Sept. 20 and 22, according to TmoNews. All rumors seem to point to a single Sept. 20 release date for both the budget iPhone and iPhone 5S.

What do you think of the iPhone 5S? Would you consider purchasing an iPhone 5S over Apple’s cheaper iPhone offering this year? Do you think Apple will release the iPhone 5S and budget iPhone on the same date? Let us know your thoughts on the iPhone 5S in the comments section below.

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