Exporting pictures for Ipad Question

Hello Folks,

i just recently got an ipad 2, and during the summer i want to start uploading my favorite pictures.

One question
when i export the pix from lightroom

What is the smallest dimension (and other settings to) i should export them to, still having great quality?

I really wanna enjoy pictures on the ipad, so i want to have the best picture quality, but with the smallest file size possible.

I need to optimize space as much as i can, so i dont want to export big jpg files if there is no reason to

any advice would be greatly appreciated

thanks

matteo