Wrong. Samsung has updated the OS and you can now install apps on your SD Card. I did this with my S4 just last week. Also if you see, my post was from May. It's end of September now.
Yes that is correct. Canadian S4s have unlocked boot loaders meanwhile the ATT one is locked. Still does not make that big of a difference seeing as they are both the same models just difference one is unlocked BT and the other one has a locked BT.