About a month ago, we announced new APIs that let developers create pages in specific sections in OneNote. Since then, we have also updated Office Lens app to use these APIs. What we are hearing from our users is that they love the ability to control where the pages get created.
We have 2 new Channel9 videos below that will walk you through how to have the same functionality in your apps.
Enumerate notebooks list and sections list: Windows Phone Edition
Create a Page in a specific section: Windows Phone Edition
You can find more OneNote API videos at the OneNote Video Series on Channel9.