Sangeeta Mudnal, Jeff Zhang and other members of the development team answered quite a few of the queries. Their answers about how much of the Office on iPad code is shared and how it was developed were especially interesting, to me.
I've culled a few key questions and answers from the AMA. (I've paraphrased the questions.) Here they are, in no particular order:
Did Microsoft use C# and/or Xamarin to write the Office for iPad app or is it native Objective C?
"The Office for iPad apps are completely native! The core logic, such as Excel’s recalc engine or Word’s text layout code, is C++ code that we compile and share across all of our platforms. The UI is all completely native Objective C; we did not use Xamarin or C# to develop our UI. As for using C#, we do use some C# for internal tools. I imagine we’ll continue to use the appropriate native frameworks for each platform (UIKit for iOS, AppKit for the Mac, etc)."
Has your iPad work delayed the next version of Mac Office? I'm still waiting for a real Cocoa version of Office (AFAIK 2011 still uses Carbon primarily, despite a few Cocoa UI elements).
"The code for Office for iPad and Office for Mac is shared, as the development platforms for both are very similar. :) The iPad work required us to create an all-new UI and to redesign the interface between UI and the internal logic. That work actually helps us with de-Carbonizing Office for the Mac, instead of delaying or hindering it. We're able to create new Cocoa UI on the Mac and tie it into the new logic interface now."
(Me: In other words, no one will still say exactly when Office for Mac is coming. The Office engineers provided a handy animated GIF, an image of which is embedded at left, to emphasize that point.)
Will it be possible to write extensions for Office for iPad using the new Apps for Office model?
"Sections 2.7 and 2.8 of Apple's App Store Review Guidelines emphatically state that downloading, installing, or launching any sort of code other than your app's own code is prohibited. I don't know if Apps for Office would be allowed in the iOS App Store."
Will Microsoft add Outlook for iPad to the suite?
"Currently, for work email, we have OWA for iPad. To read Outlook.com email (previously known as Hotmail), you can use the iPad Mail app."
When will Office for iPad support printing?
"Print is a high demand feature that we intend to introduce in due course."
Are there new features for Excel for iPad coming, including add/change conditional formatting and comments?
"Unfortunately, I can't really comment on what's coming up, but I will say two things: One of the great things about Office for iPad being a subscription is that it means you'll keep getting frequent updates. Both of the features you mention are definitely on our roadmap and are things we on the product team use often.We just need to prioritize them properly with all of the other things people are asking for, which is why feedback like this is great."
What about support for mathematical notation on Office for iPad or Office for Mac?
"We've heard from several students like yourself that equation support would be useful. We're looking into it."
Will Microsoft add Office for iPad support to Office 365 A2 Education plans?
"Not currently. The rule of thumb is that Office for iPad is included in O365 plans that include Office for PC and Mac. If you would like to use Office on the iPad, we recommend the A3 or A4 plans."
How does Office for iPad measure up to Apple's iWork?
"As for competing with iWork, I think the two products really have different aims and audiences. There's some overlap, but the variety of user needs is really very broad. In that sense, Office and iWork more complement each other than compete with each other."
Is Microsoft planning to deliver Office on Android tablets?
"We want to bring great Office experience to our customers who want to be productive on their tablets. In the future we will bring Office apps to the Windows Store and other popular platforms, including Android tablets. No dates yet... "
Does Microsoft expect the iPad to replace using the laptop for Microsoft Office use?
"When multitasking is required, or you need to combine information from multiple documents, or you want pixel perfect precision, then Office on a laptop with keyboard, mouse and multiple monitors is the better solution and will not be replaced by iPad or tablets scenarios."
Is CEO Satya Nadella "the MSsiah like the tech media is portraying him?"
"The decision to ship Office for iPad was made before Satya became CEO. Steve Ballmer approved the plan to ship Office for iPad."
Would you rather fight 1 horse-sized iPad, or 100-iPad sized horses?
"Definitely 100-iPad sized horses. We have an army of iPads on standby waiting to strike back."