Ever since leaks pointed to iPhone 5's Sept. 12 debut, anticipation surrounding the next-gen Apple smartphone has reached fever pitch. 

We give you a round-up of the top 5 rumors that may hold true for the next-gen Apple smartphone. 

5. New Earphones

The latest rumor about Apple's iPhone 5 that hit the Internet came from a Vietnamese site Tinhte.vn (translated). According to the site, Apple is set to introduce redesigned headphones with its next-generation iPhone. Also, the site claims that the the Foxconn Vietnamese factory is manufacturing the earphones and the cable includes the company's iconic signature "Designed by Apple in California. Assembled in Vietnam." Folks at the Vietnamese Web site are convinced of the authenticity of the earphones because of its superior build quality. According to them, the new earphones will be smaller and do not hurt the ear when worn. Apple has never made any significant change in the earphones since its introduction of the first iPod in 2001 and, therefore, a possibility to receive its much-deserved overhaul exists.

4. NFC

An NFC-enabled iPhone 5 is perhaps one of the most debated topics on the Internet. While some recent leaked images from Apple.Pro claimed that the Cupertino tech giant will certainly pack in a front-facing NFC chip, folks at Anand Tech had absolutely rejected the claim. Additionally, Apple won a major patent on March 6 for its iWallet feature, which relates to establishing financial transaction rules for controlling a subsidiary financial account along with giving users the ability to see their entire credit card profiles, view statements and messages from their banks, and even set parental controls for their children.

"The idea of the iWallet is to let individuals buy things by merely using their iPhone 5 or any other device of Apple. This means that the user does not need to bring a credit card to a store with NFC support," the report explained.

iWallet will also leverage Near-Field Communication technology to complete credit card transactions directly on the phone.

While we aren't certain if this technology will finally feature in the iPhone 5, we think NFC has a good possibility of making it to the device.

3. LTE

Last time, the company could not compromise the design of the iPhone 4S, however, this time Apple may change the game without hampering the look and feel of the next-generation iPhone.

In April 2011, Apple CEO Tim Cook, during the company earnings conference call, acknowledged that the company could not incorporate LTE support at the expense of the overall design and weight of the iPhone 4S. However, reports indicate that the 4G LTE feature will be packed in with the next iPhone, even if the company has to make the device a little thicker to accommodate a larger circuit board and a bigger battery.

In a report published by DigiTimes in March, a few unnamed sources within Taiwan-based smartphone manufacturers claimed that the next-generation iPhone is "very likely" to contain an embedded 4G LTE radio. Also, Verizon, in its latest report, reveals that it plans to unveil only 4G LTE capable smartphones for the rest of the year, which again confirms the anticipation that Apple will release a 4G-enabled phone.

Additionally, Thomas Seitz, a Jefferies & Co. analyst, claimed that the new iPhone is likely to be LTE capable and if it supports LTE, Verizon has a better stand to attract at least some customers away from AT&T.

"We believe this network advantage could lead to a share shift towards Verizon, primarily at AT&T's expense," Seitz said.

While we don't know if Verizon will get the better of AT&T and vice versa to win the game, the possibility of LTE in iPhone 5 is very likely.

2. Nano SIM

In July, Financial Times reported that the mobile operators in Europe were stockpiling nano-SIMs, which were especially designed for Apple's next-generation iPhone.

The nano-SIMs are 40 percent smaller than the current micro-SIMs, and once released, will replace the micro-SIM cards used in the current iPhone 4S and iPhone 4 along with other leading smartphones.  The nano-SIM will help Apple save some more space in the tightly designed interior of its next iPhone and we believe that nano-SIM is very likely to feature in the iPhone 5.

1. 4-inch Retina Display with In-Cell Technology for Lighter iPhone 5

With a bagful of monstrous Android smartphones like the Galaxy Note, Note 2, Galaxy S3, and HTC One X available in the market iFans too need something bigger.

In May, the Wall Street Journal said that that the next iPhone would have a screen that's at least 4 inches. Additionally, in August, Reuters  reported that LG has already started mass production of a display that integrates "in-cell multitouch technology."  

In April, DigiTimes reported that Sharp and Toshiba Mobile Display (TMD) had started working together for Apple to produce an in-cell panel Q2 2012. While Sharp is manufacturing the in-cell panels at its 5.5G lines, TMD would use its 6G lines for the production of the panels, said the report.

Moreover, some earlier reports suggested that Apple will come with a Retina Display, giving Apple a definite edge over Android phones. Rumors  also suggest that Apple may  replace the qHD Retina Display with a TrueHD.