Apple's iPhone 5s hit the shelves on Friday, so teardown experts iFixit jetted over to Australia to get their hands on the iPhone 5s before anyone else. What did they do with it? They destroyed it, of course.

iFixit has published a step-by-step walkthrough of the process of taking the iPhone 5s apart, to get to know how the iPhone 5s works and what's going on inside the new device. Here are some highlights from the teardown.

See: iPhone 5s review

Inside the iPhone 5s: Battery

The iPhone 5s has a 3.8 volt, 5.92 Wh, 1,560 mAh battery. That's slightly bigger than the iPhone 5's 3.8 V, 5.45 Wh, 1,440 mAh battery, whole the Samsung Galaxy S4 has a 3.8 V, 9.88 Wh, 2,600 mAh.

iFixit notes that Apple seems to have added lots of adhesive to stick the iPhone 5s battery in place, unlike the minimal adhesive used in the iPhone 5, making it tricky to remove.

See: iPhone 5s availability

Inside the iPhone 5s: Touch ID fingerprint sensor

One of the key new features in the iPhone 5s is the Touch ID fingerprint sensor, which is integrated into the Home button and can be used to unlock the iPhone 5s or authenticate your Apple ID.

The fingerprint sensor is a CMOS chip, and is "essentially a bunch of very small capacitors that created an "image" of the ridges of your finger," writes iFixit. The technology was developed by Authentec, a company that Apple purchased in 2012.

iFixit expresses its concern for the durability of the Touch ID technology. The teardown experts say that they they are worried about how well the sapphire crystal, which covers the sensor, will be able to protect the CMOS sensor from degrading over time.

Inside the iPhone 5s: Camera

The iPhone 5s has a significantly improved camera. It's still 8-megapixels, but the pixels are bigger than they were in the iPhone 5, and the camera has an aperture of f/2.2 compared with f/2.4 in the iPhone 5. These improvements aim to boost low-light performance.

See: iPhone 5s new camera features

Inside the iPhone 5s: A7 processor

Apple's powerful A7 processor is another key selling point for the iPhone 5s. It's the first 64-bit mobile processor, and is based on ARM's ARMv8 instruction set. According to Apple, the new processor will mean double the speed and performance compared with the A6.

"The modern ARMv8 instruction set was designed for a 64-bit architecture," says iFixit. "It does away with the legacy support of the last 20 years, which increases efficiency, improving performance without sacrificing battery life."

Speculation is that Apple is using the same amount of RAM, 1GB, but upgraded to LPDDR3, which has a higher data rate, greater bandwidth, better  power efficiency, and higher memory density.

Inside the iPhone 5s: M7 coprocessor

Initially absent from iFixit's iPhone 5s teardown was the new M7 coprocessor, which is designed to offload work from the A7 processor for improved power efficiency. Particularly, it gathers information from the accelerometer, gyroscope and compass. This could mean a new generation of fitness apps are on their way, too.

iFixit says that the M7 coprocessor is buried beneath a neoprene-looking cover within the iPhone 5s, which is why it was tricky to find.

See: The M7 motion coprocessor in the iPhone 5s is a big deal

Inside the iPhone 5s: Dual LED True Tone Flash

Another new feature in the iPhone 5s is the dual-LED flash, which also helps to improve the photographs users can capture with the iPhone.

The iPhone 5s uses two LEDs, a white one and an amber one. There are 1000 flash combinations programmed in to the iPhone 5s to help automatically produce the optimal light balance for a particular scene.

iPhone 5s: repairability

Overall, iFixit gives the iPhone 5s a repairability rating of 6 out of 10, with 10 being the easiest to repair. 

Additional reporting from John Cox, Network World US.

See also:

How to set up a new iPhone 5c or iPhone 5s

Apple's Cook, Ive & Federighi talk iPhone 5s, iPhone 5c, iOS 7 and future products

Should I buy an iPhone 5 or buy an iPhone 5s or iPhone 5c?