A subtle new feature that’s been added to the built-in Mail app in iOS 9 allows you to mark up PDF and image file attachments. With the built-in markup editor you can add lines, shapes, arrows, and even drop in your signature. As an added bonus, if you’ve created signatures in Preview on your Mac they’ll be automatically synced via iCloud (providing you’re signed into the same iCloud account on both devices) and available to…
