There are plenty of reasons why you might want to schedule an email to send at a later time - perhaps it is something you don't want to forget but it is too soon to send immediately, maybe you are emailing somebody in a different time zone and you want them to be awake when they receive it, or maybe you are negotiating with unsavory characters and have a scheduled email of incriminating evidence as insurance.
Until now you could only do very simple formatting of your email text - you could make it bold, italicized or underlined. iOS 13 adds rich text formatting, giving you many more options add style to your message with. Now you can quickly change font and text size and color, add numbered/bulleted lists and justify the text.
To use the format tools, start a new email from your iPhone or iPad's Mail app and tap the "<" button.
iOS 13 has improved the Mail interface - instead of tapping and holding until a menu appears and then scrolling left and right to find your tool (which you can still do if you prefer), there is now a much more aesthetically pleasing and useful toolbar that you can open with a single tap. From this bar you can format your text, insert photos, take a photo, attach files, scan a document and insert a sketch.
After a less-than-stellar debut, Apple has continued to improve upon its Maps app with each new iOS iteration, including iOS 13. In addition to adding the Look Around feature (equivalent to Google's Street View) and letting you automatically share your ETA, iOS 13 also tweaks the Favorites feature and adds a Collections feature which lets you create a list of locations that you can share.
Animoji debuted with iOS 11 as fun Messages feature involving animated characters that use your iPhone's front-facing camera to mimic your facial movements and expressions. iOS 12 introduced Memoji which are basically customizable human Animoji. iOS 13 now lets you use both Memoji and Animoji as your profile picture. Not only can you use them as your own avatar, but you can create Animoji and Memoji profile pics for your contacts as well.