Create bulleted list in iOS Mail
Until Apple offers the ability to add some basic controls (eg. bold, etc.) on the iPhone/iPad (without the keyboard) it's not possible without copying and pasting from a previous message.

You could create a draft with the different types of list to copy and paste and use that.

Of note: some third party apps can help with this: eg. MarkdownMail just released today by Second Gear Software ($1.99) or any other app that will allow you to create HTML.