A previous report by Digitimes stated the next iPhone was going to sport a higher resolution display and 512MB of RAM. With the announcement of the iPhone 4, the Retina Display verified that rumour. The 512MB of RAM story hasn’t been verified until now–as Apple confirmed this during a 2010 WWDC session (Session 147, Advanced Performance Optimization on iPhone OS, pt 2).
The iPhone 4 Has 512MB of RAM
According to the following slide image from the WWDC session via @rzhale, here is the breakdown of RAM on iOS devices:
iPhone 4: 512MB
iPhone 3GS: 256MB
iPod Touch (3rd Gen): 256MB
iPod Touch (2nd Gen): 128MB
iPhone 3G: 128MB
So, if we take this into consideration it’s now very clear why the iPhone 3G cannot “support” multitasking from iOS 4. I’m sure it would work–but it won’t be a pretty experience. My old iPhone 3G is already sluggish as it is right now. I’d hate to see how fun multitasking will be. What’s surprising to me is that the iPad has only 256MB of RAM, but it’s amazingly fast–most likely a result of the A4 chip.