The latest iOS update, the 11.1 came out to correct some bugs, such as the security problem in WiFi, but at the same time, it did not come out immune to having some that although they are not serious, they are real headaches since they affect the to write.
In this case, the letter “i” is being replaced by the letter “A” or the symbols, “#,” or “!” Plus another unicode. Of course this only happens if the autocorrector is activated, so it is necessary to erase it and write the “i” manually. This does not happen if it is copied and pasted into iMessage, Twitter and Instagram.
Apple is aware of that problem and are already fixing with an upcoming update without date yet, although it does not happen to all users of the iPhone, iPod Touch and iPad. An official alternative is to enter the settings menu, “general” section and select “keyboard”, touch “replace text” and in the “+” symbol, write “I” and “i”.