[grunt0300]

Is there a difference between the IPhone4 16gb & 32gb, other than the extra memory, and is the IPhone4 much faster than the IPhone3GS ? Thanks.

[Username00089]

Just the memory with 16/32GB. The "much faster" question is more a matter of
opinion. I used the 3GS for a year and I find my i4 to be pretty faster than my 3GS was.

[GolfnCPA]

I opted for the 32GB because of the high quality video and picture resolution. Figured it would use more space to store much of this.

[Roo Zilla]

The i4 is significantly faster than the 3GS, but the difference isn't as big as from the 3G to the 3GS. Some people say it feels the same. Sense of speed is a subjective matter, so your mileage may vary.

[pilsbury]

Isn't the processor of the i4 roughly double that of a 3Gs, and wouldnt it make it that much faster? My i4 is much faster than my 3Gs.

[Roo Zilla]

Isn't the processor of the i4 roughly double that of a 3Gs, and wouldnt it make it that much faster? My i4 is much faster than my 3Gs.

The 3GS uses a Cortex-A8 clocked at 600Mhz. The i4's A4 is packaged with the same processor at (best guess) 800Mhz, but it's made on a newer manufacturing process which uses smaller transistors and actually uses less power. Much more than the 200Mhz difference in processor speed, the double RAM (512MB vs. 256MB) affects performance. Much more can be kept in system memory instead of swapping to and fro from the flash memory, which is many degrees slower in speed. This is the reason why browser skins like Atomic Web and Perfect Browser work so well, in addition to multitasking.

Like I said though, speed observations are a subjective experience. Some people can't tell the difference.

[pilsbury]

RAM, that's what I was thinking of-thanks Roo.

[iBlack11]

What did apple exactly say the difference was better 3G & 3GS?

[Roo Zilla]

What did apple exactly say the difference was better 3G & 3GS?

The difference between iPhone 3G and 3GS was huge. Aside from MHz increase from 400Mhz to 600Mhz, there was a generational improvement in CPU architecture. Aside from new SIMD instructions which help performance on properly coded software (and even improperly coded software), the Cortex-A8 introduced superscalar capability to the ARM line of CPUs. That was basically the difference you saw back in the early 90's when the original Pentium processor was introduced. Superscalar allows for multiple instructions per clock cycle, which greatly improves performance. Next year we should start seeing Cortex A-9 which will introduce out of order execution. OOE should offer another big bump in performance without increasing clock speeds. Hopefully by the time the next iPhone is introduced, we will see dual core Cortex-A9 with on die memory controllers on a newer manufacturing process, 32nm. That could conceivably allow for about 50% increase in performance at the same clock speeds as the A4 currently in iPhones, while maintaining a very similar power profile.

[Roo Zilla]

Since I recently got my iPhone jailbroken again, I've noticed a few things. The boost in memory I think affects jailbroken phones more than anything else. Before, some Cydia apps would slow down my phone. For example, on my 3GS, using Winterboard, LockInfo, and Activator would slow down my browser. There would also be some jerkiness in the UI every now and then. It's almost impossible to tell now. The only slowdown I've noticed is after the initial respring, after a minute it goes away and feels fine.