If we go native ... which platform do we target first?

iOS

Our stats show iOS as the dominant platform for our existing mobile users.
A lot of noise about iPad becoming established in the classroom - if it is true, we would want to capitalize on that.
Stats elsewhere suggest the Apple users are more likely to spend (revenue in AppStore was over double that in GooglePlay)

Android

Age-profile for Android usage is closer to our target market
Our stats suggest Android has a significant foothold in rapidly expanding markets.