Yes. We did this with no problem. Two pieces of info though:
1) In the app, it will show that your tickets expire in two weeks. Do not worry. The dates rolls forward every day until you enter the park on your first day. Then that dates holds.
2) You will still need to present your paper tickets at the turnstiles, at least the first entry. I tried the app version and right after they scanned, the CM asked to use the actual paper tickets. After that, I just always had the paper tickets out for entry.