Ipad resolution IS 1024 x 768
Here is a post that is a more like a small tutorial:
Ipad Resolution is 1024 x 768 at 132 Dpi as listed in Apple web site.
And the aspect ratio of the screen is not 1:1, it is 4:3 as in old CRT monitors. A 1:1 aspect ratio is a perfect square and if you look at the Ipad you can tell at a glance that its monitor is not a perfect square clearly.
If those people from Interfacelift list those wallpapers as 1024 x 1024 (1:1 aspect ratio) is because of the automatic rotation of the Ipad and that must be to compensate for the aspect ratio rotation by changing from the vertical position of the Ipad which is portrait orientation but if you flip it 90 degrees then it is in landscape orientation.
The wallpaper that was shown in Apple's presentation was designed in portrait mode, I think that you can design a wallpaper for the Ipad that is 1024 x 768 but vertical for portrait but it won't look as good in landscape and the opposite which is that you could design a wallpaper for the Ipad at 1024 x 768 resolution with landscape orientation an it would look good in landscape mode but it may not look so good in portrait mode when the device is rotated.
I haven't have access to an Ipad yet to know what the computer does with those wallpapers when it rotates, maybe it letterboxes them, maybe it stretches them this or that other way or maybe it does other things to them.
Different things can be done to this depending on how the device was programed by Apple, many different things and the device may have different ways to handle that if it has different settings that the user selects, it depends again on how it was programmed.
My guess is that Interfacelift is asking for 1024 x 1024 because they found that it can be a good compromise for the orientation change problem but again that could make the image stretch or shrink in one way or another or letterbox in one way or another depending on how Apple programed the machine but it will still be a compromise too, that's their solution but you may do the wallpapers in one of those 3 ways, 1024 x 768 portrait, 1024 x 768 landscape and perhaps Interfacelift compromise of 1024 x 1024 for both orientations, that's up to you but the device true resolution is still 1024 x 768 with a 4:3 aspect ratio.
You are not the only people to get confused by this, when I visited different forums and saw people talking about wallpaper I saw a lot of confusion about total resolution versus Dpi resolution and vs aspect ratio.
Dpi resolution is determined by the total amount of resolution of the display (in this case 1024 x 768) and the real physical size measure of the display in inches or any other measuring system but if you use a different measuring system to determine Dpi you will have to convert the physical measures of the display to inches first because it is Dpi which is Dots per
inch.
This means that if you have an equal resolution and you have different sizes of monitors the Dpi will be different in those dissimilar sizes monitors. If you have a small screen let's say 7 inches diagonally with that resolution and you have a 12 inch display with that same resolution the small display will have a higher Dpi than the large display.
The aspect ratio is also something that confuses people a lot, it just means that if you have a 4:3 aspect ratio (old squarish monitors do) you have to take those 1024 pixels and divided them by 4 and then multiply them by 3 and you will get 768 pixels, that's why you cannot use something like a 16:9 resolution of HD in a 4:3 monitor because if you use a wallpaper with those pixel resolutions it will stretch enormously and it will look bad.
If you have a 16:9 aspect ratio (the new HD widescreen monitors) you have to take that resolution (1920 for example), divide it by 16 and multiply it by 9 and you will get 1080 pixels and is the same for other resolutions with those 4:3 or 16:9 aspect ratios and for other aspect ratios like 16:10 (Apple regular widescreen displays for example) you calculate it in the same way.
The general idea is to maintain the pixel
as a square pixel and that's why the pixel proportions of those different resolutions is different in the different aspect ratios of different monitors because if you don't follow those pixel proportions your images will be distorted either vertically or horizontally.
Here is a little table to use as a reference that contain most mayor resolutions used today:
16:10 Aspect Ratio
3840 x 2400
2560 x 1600
1920 x 1200
1680 x 1050
1440 x 900
1280 x 800
Near 16:10 Aspect Ratio (Pixel is not perfectly square but close)
1280 x 768
16:9 Aspect Ratio
1920 x 1080
1600 x 900
1366 x 768
1280 x 720
4:3 Aspect Ratio
2048 x 1536
1600 x 1200
1280 x 960
1152 x 864
1024 x 768
Near 4:3 Aspect Ratio (Pixel is not perfectly square but close)
1280 x 1024
Iphone 4:3 aspect ratio
320 horizontal x 480 vertical. The wallpaper is always vertical in the Iphone cause it doesn't rotate in landscape mode (photos do rotate and they are letterboxed)
Ipad 4:3 aspect ratio
1024 horizontal x 768 vertical in landscape mode
768 horizontal x 1024 vertical in portrait mode
I hope that that helps to clear a bit of this confusion.
