before you even try, what revision of ios is your ipad now on now?
There is only one place to download apps and tweaks. It's called Cydia and it functions like the App Store does for Apple. It's installed when you jailbreak.I am using 8.1.3
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Any recommendation good site to download software to be used thanks
You can't jailbreak 8.1.3 currently. You'll have to wait.