I've just deleted the lame AC app for iPhone as it doesn't offer my iPad any features I don't already enjoy thanks to flightstats.com (email/text notifications) or aircanada.com (OLCI, eUpgrades, etc).
Having been an iPad user since Apr 2010, I'm left in awe that a dedicated iPad app has yet to be released as the additional screen real estate might be useful for tracking flights or perhaps the declining value of Aeroplan reward miles.
As long as there isn't a PlayBook app before an iPad one, I shall be content with the other workarounds in the interim.