You will find the necessary tools in the new Draw tab, which include a pen, a highlighter, and an eraser.
By Ng Chong Seng -
Before this, if you want to doodle in Word, Excel, or PowerPoint on iOS, you need to have an iPad Pro and Apple Pencil. But after the most recent Office update, you can now write, draw, and highlight documents on the iPhone too, but using your fingers.
More specifically, you’ll find the necessary tools in the new Draw tab, which include a pen (with adjustable line thickness and color), a highlighter, and an eraser. The annotation features not only work in Word, but also in Excel and PowerPoint, so you can markup freely over cells and slides as well.