This week's book giveaway is in the OCAJP 8 forum. We're giving away four copies of OCA Java SE 8 Programmer I Study Guide and have Edward Finegan & Robert Liguori on-line! See this thread for details.
Bear is right, "yes, both" is the obvious answer. But I may suggest that the app-store is as important. The market has decided that "apps" are critical, and no other smartphone/tablet platform has anywhere near the market share.
Today, I believe (IMHO, etc.) that the iPad has no real competition. If you want a real tablet, or if you want to develop for a tablet, the only one to care about is the iPad. I expect than in a few months, the answer will be "iPad or iPad3"
I wish the Android Tablet folks would get their act together, as competition is good for all of us. But today, there is no real competition. Even if the Android hardware and software is as good as IOS/iPad, the app-store is a huge advantage.