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First you should edit your post because there is illegal stuff in it.

Second if you restore / upgrade your iPhone you will loose ALL your tweaks/functions from Cydia. So he can't use it without a jailbreak.
 
It is in iTunes, but without appsync he would not be able to install it back on his iphone. For appsync you need Jailbreak.

The same way you can torrent giant app packs from online and drag them into iTunes, but you would not be able to install without appsync.

And it's illegal.
 
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