im thinking of buying an ipad but i already have an ipod with apps i have already paid for,if i buy the ipad (using the same itunes account) will i get charged again for those apps or not?
No, but make sure you use the same AppleID for both devices.
No, as long as your iPad is configured using the same Apple ID all of your apps can be installed on either device.
In almost all cases, no, once you've bought it you can redownload it on any device. There are however a small number of apps that have specific versions for iPhone/iPod and iPad that require you purchase both versions.
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