I am planning to buy an iPad 3. My choices are,
I'm so confused to select my best choice.
Actually the problem is, some of my friends telling that, the performance and the OS update support depends on the memory size only. That is, the higher memory capacity device has high performance with future OS update supports (Because, the new updates may eat more memory). So they are suggesting the iPad 3 - 32GB (wifi alone).
Is their answer right?
All 3rd generation iPads perform pretty much identically, because they have the same CPU, GPU and RAM (memory). Battery life varies between the Wifi and Wifi+4G models (with the 4G models getting a bit less battery life in exchange for a bit more connectivity).
The 16/32/64gb figure refers only to how much data (music, videos, books, apps and associated stuff) you can store on the device.
I suspect when apple drop OS support for the 1st generation iPad, they'll drop them all at once, no matter how much storage space they have.
You appear to be mixing up Memory and Storage Capacity. The amount of memory (speicifically the RAM) is the same regardless of the storage capacity of the model you choose (or is when comparing different models from the same generation). This memory, (which is something like 512Mb or 1Gb, I forget which but it's actually not that important) is important when it comes to performance, but not in the same way as for PCs, and because there is nothing you can do about it, they all have the same, it's not worth including in any purchasing decisions.
In terms of how much Storage Capacity you might need (16/32Gb) it's a matter of what you will use it for, rather than anything else. Consider that the same OS is supported on an 8Gb iPhone 4, the base OS is less than 1Gb total and a ralatively minor part of your total storage. Obviously the percentage of your storage that the OS takes up is doubled each time you half the capacity options, but it would only ever be an issue for you in terms of upgrades if you completely filled the iPad with apps and data, and only you can know what usage you will do as to if that is likely. Games and video editing/lots of photos/music etc will eat up space, other apps less so. I have a 16Gb iPad adn was initially concerned it would not be large enough given the size of new retina apps, but that is unfounded. Having said that, I have no video or music on it, I stream all that.
Future OS updates will be carried out (in all liklihood, if the past is any indicator of the future) on a generational basis, not on specific models within that generation. So your your original iPhone 4 supports the latest iOS release, you can be sure that it is all models of that phone that have the support, not just the ones with more storage.
Nothing is like that. I am having "8GB-iPod Touch" bought 3 years back but it runs the latest iOS-5.1.1 very fine.
iPad storage capacity is just about the amount of storage of data.
Go ahead with your budget. Its not gonna affect future versions of iOS.
The statement of your friends is incorrect. The OS is installed on a separate partition that is the same size on all iPads and makes no change in the speed of the device.
