Use OneDrive Scanner to Add Pictures and PDF's Straight to One-Drive

There is an easy way to add pictures straight to your onedrive. In addition, you can choose to have onedrive camera automatically convert pictures of documents to pdfs.

Here is an instructional sheet on how to do that. 

Here's a video of someone showing you how. 

OneDrive (iOS) - Creating a multi-page PDF file and sharing it - YouTube