Changing the order of recipient's name
In some languages, such as Korean, the family name precedes the given name. So displaying a people's name as 'first name + last name' is very weird. Especially, when typing a recipient's name in 'To' field, the last name (family name) usually precedes the first name (given name).
Even in gmail, gmail shows the peoples' name in the order of 'last name + first name' when a user sets the location to Korean.
In deed! Japanese, Korean, and Hungarian too :)
Jaeyoun Yi commented
It's critical for 'To' field.