ipad 3 to ipad mini isn't an upgrade when it has no retina, half the RAM, A5 chip
It's unknown how much RAM it's got. Not all A5 chips are equal - it depends on the product.
Also, the iPad 3's also got an A5 chip, really. The -X just stands for the graphics - and we're not talking about increased performance, we're talking about 'just enough to run the retina display'.
In fact, if you think about it: the A5X chip has to push four times as many pixels as before, but it's only twice as powerful. This means, relatively, the A5 chip with a 1024 x 768 display, is still twice as powerful as an A5X chip which needs to push a 2048 x 1536 Retina display.
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I think it's a very good question, honestly. There are only a few differences between the iPad 3 and the iPad mini, namely: the bigger Retina display, A5X chip, FaceTime HD and the Lightning connector.
If you sell your iPad 3, you'll miss the Retina display with its A5X chip. In return, you'll get a 1024 x 768 that, quality-wise, is in between the iPad 2 and iPad 3. It's obviously a tad smaller too. You'll get an A5 chip instead of an A5X chip. This means graphics performance will get better and CPU performance stays the same on the iPad mini.
Graphics performance gets better because the A5X chip is only twice as powerful as the A5 chip - a Retina display needs four times the power. So basically, a non-Retina display device with an A5 chip, is more powerful than a Retina display-device with an A5X chip.
You'll also get the new Lightning connector, which will be Apple's new dock connector for the years to come, and FaceTime HD for HD video calling.
So, yes, you'll lose the Retina display but in return you get a device that is smaller, lighter, thinner and is equal or better in every other way possible.
I am really having a hard time deciding if I should do this. I don't really play any games other than things like Angry Birds, etc so that is not an issue. And as I recall the iPad 2 was pretty darn fast.
I like the iPad Mini because of the size, the new connector, and the upgraded cameras...however, I also like the idea of getting about $100 in cash for the "upgrade" from the iPad 3.
What do you guys think about going from an iPad 3 to an iPad mini?