If you don’t regularly check your email throughout the day, the unread badge count on your iPhone or iPad is an indispensable part of your workflow. When it works, that is. If your iOS Mail app is like mine, it often shows a lone unread email badge even when everything’s been read, which can get annoying.
There’s a simple explanation for it that doesn’t involve nuking your account and starting over (believe me, I’ve tried). It has to do with rules. While you can’t actually create mailbox rules on your iOS device, you can set them up on the Mac, which is where the trouble starts.
Mail rules are basically if-this-then-that sorting and organizing for your inbox. You can have messages automatically move, redirect, forward, or flag based on the sender, subject, or contents, and it’s very useful for keeping clutter out of your inbox. However, since Mail Rules can only be created on the Mac, the iOS app struggles a bit and that’s where the trouble comes in.