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Apple Watch runs 'most' of iOS 8.2, may use A5-equivalent processor

The Apple Watch is using "most" of iOS 8.2, with a new subsystem called "Carousel" in place of the Springboard homescreen found on iPhones and iPads, developer Steve Troughton-Smith said on Thursday, also suggesting that the Watch's S1 processor appears to be equivalent to the Apple A5.

Posting on Twitter, Troughton-Smith noted that the Watch firmware contains a PowerVR SGX543 driver. The SGX543 is the same graphics component found in the A5, which Apple first shipped with the iPad 2 and iPhone 4S back in 2011.

The S1 though is a much more compressed chip design, building everything the device needs into a system-in-package surrounded by resin for extra protection. Apple has said relatively little about the technology beyond that, making it difficult to gauge performance.

The Watch firmware is not officially considered a version of iOS. Since it has to interact with a paired iPhone, however, it makes sense for it to be founded in the same general codebase.

Troughton-Smith further observed that all of the Watch Faces are stored in a single framework, called NanoTimeKit. Those Faces use SpriteKit graphics, but animated faces like Mickey Mouse apply OpenGL for rendering.



26 Comments

fallenjt 4056 comments · 13 Years

imagine the  performance of iPhone 5S inside this little puppy...very impressive.

fallenjt 4056 comments · 13 Years

Quote:
Originally Posted by TheWhiteFalcon 

Ugh, the A5 has lived way too long.

4S is still used by many out there. What's wrong? It's a damn watch and doesn't need all the power of the latest chip. You like to put 4.0L V-8 engine in a Fiat500?

scottjd 64 comments · 11 Years

Yes, it may be impressive but I'm hoping it's not the same exact chip and just smaller. I would hope apple would make it more energy efficient and also hoping it's more of a 64bit compatible. Since Apple is forcing all apps to go over to a 64 bit structure it would only make sense that all future Apple devices are also 64 bit. I would hate to have to buy another watch in 2 years because they force it over to 64 bit if it's not now compatible.

rcfa 1123 comments · 17 Years

Might have been meaningful to put a 64-bit ARM in there without 32-bit backwards compatible instruction set, since as I remember from the A7 introduction, it was said the 64-bit instruction set was designed to use less power, and that 64-bit apps use less power. On the watch backwards compatible 32-bit instructions wouldn't be required, so all that could be left off the chip. It's a stretch to assume a specific CPU core just because of the presence of a certain GPU.