Guide to Downgrade iOS 4.3.5 To 4.3.4, 4.3.3, 4.3.2 Or 4.3.1 on iPhone, iPod Touch and iPad

Today Apple iOS 4.3.5 has just been released for iPhone, iPod Touch and iPad to fix a security issue with certificate validation issue. But if you accidentally updated your firmware to 4.3.5 and you had saved your SHSH blobs for iOS 4.3.4, 4.3.3, 4.3.2 or 4.3.1.




Geohot has the guide on how to downgrade from iOS 4.3.5 to any of  iOS 4.3.4, 4.3.3, 4.3.2 or 4.3.1.

Just follow the step by step procedure here at Geohot's blog.

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iPhone 4 Gyroscope - Teardown to the Silicon

Apple first announced the iPhone 4's gyroscope at WWDC 2010, but it was largely overshadowed by other big players inside the phone -- the A4 processor, Retina display, and external antennas. A lot of technology gets stuffed into vibrational gyroscopes (the type found in the iPhone 4), yet a casual observer may barely notice the chip itself, let alone the phenomenal contents within it. iFixit and Chipworks have partnered to show you exactly what's inside these little gems:

According to Wikipedia's definition, "A gyroscope is a device for measuring or maintaining orientation, based on the principles of conservation of angular momentum." The key phrase is measuring or maintaining orientation, which is the exact reason an iPhone 4 contains one of these gizmos.





http://www.ifixit.com/Teardown/iPhone-4-Gyroscope-Teardown/3156/1

http://www.chipworks.com/iPhone-4-teardown.aspx 

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Apple iPhone 4 Disassemble Instruction Guide

The phone uses the 1 GHz ARM Cortex A8 core, much like its bigger sibling, the iPad.

 * Unlike the iPhone 3GS and iPad -- which are both equipped with 256 MB of RAM -- the iPhone 4 has a whopping 512 MB.

 * The AGD1 is the new 3 axis gyroscope that we believe is designed and manufactured by ST Micro for Apple. The package marks on this device do not appear to be the currently available commercial part, L3G4200D.

 * In what can only be described as a work of genius, Apple has integrated the UMTS, GSM, GPS, Wi-Fi, and Bluetooth antennas into the stainless steel inner frame.

* Broadcom provides both a BCM4329FKUBG 802.11n with Bluetooth 2.1 + EDR and FM receiver and a BCM4750IUB8 single-chip GPS receiver.
* We've identified chips from Broadcom, Cirrus Logic, Numonyx, Samsung, ST Micro, Skyworks, Texas Instruments, and TriQuint.

Here's a teardown with analysis from ifixit.


The teardown:
http://www.ifixit.com/Teardown/iPhone-4-Teardown/3130/1


iPhone 4 all torn down:
http://s1.guide-images.ifixit.net/igi/kUEKB6Y2Ah5OIfAh.huge

Disconnecting logic board connectors:
http://s2.guide-images.ifixit.net/igi/AhMYpVQZs4HfRJaG.huge

Taking out the camera:
http://s1.guide-images.ifixit.net/igi/YJLZ65WWLGtCugsU.huge

Removing the logic board:
http://s1.guide-images.ifixit.net/igi/4LvvhPsqKcwvkRE5.huge

Separating display from frame:
http://s2.guide-images.ifixit.net/igi/iDQNYymGn3MyxCRR.huge

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