Revealing mistake: When the stewardess asks April to sign her copy of the book entitled "How to Survive a Sharknado and Other Unnatural Disasters..." it's a thin book, and in the closeup as April autographs the page we can read the text and it's actually one of the versions of the "Samsung Galaxy Tab...For Dummies" book, not April's book. Also notice when Kelly Ripa shows April's book to the audience, it's now at least 4x as thick.
Visible crew/equipment: When Fin and Skye get to the hotel's roof, just before they set their bags down and then also when they rush to the glass railing, we can see the reflections of crew members on the surface of the glass safety railings.
