If you type the letter “i” and it autocorrects to an “A” with a symbol

iOS 11の「i」文字バグ

If you type the letter “i” and it autocorrects to an “A” with a symbol
If you updated your iPhone, iPad, or iPod touch to iOS 11 or later and find that when you type the letter “i” it autocorrects to the letter “A” with a symbol, learn what to do.

Try setting up Text Replacement for the letter "i"

Here’s what you can do to work around the issue until it’s fixed in a future software update:
Go to Settings > General > Keyboard > Text Replacement.
Tap .
For Phrase, type an upper-case "I". For Shortcut, type a lower-case "i."
This document will be updated as more information becomes available.
Published Date: Nov 6, 2017