Tom Warren, writing for The Verge:

Microsoft was quick to optimize its Office suite of apps for the iPad Pro and Apple’s Pencil stylus, but the company held off on any inking support in Office for iPhone. Starting today, Microsoft is updating Word, Excel, and PowerPoint for iPhone to include a new drawing tab option. Just like the Windows and iPad variants, Office on iPhone will now let you use your finger to write, draw, and highlight documents.

Another great update for Word, Excel and PowerPoint on iOS.

Because space is limited on an iPhone screen, these drawing features are a little hidden. So in order to access these drawing features on the iPhone you’ll need to tap the icon on the top navigational bar that looks like an A with a pencil cutting through it. That will trigger a pop-up on the bottom half of the screen. From there, on the top-left of the pop-up should be a drop-down menu, tap that and choose “Draw”.