How to sort contacts
Local contacts are displayed by group and then sorted alphabetically based on the first letter of their display name. If a contact’s display name starts with a non-Latin character (e.g., *, $, #, etc.), they are put in the # group. If the username is missing, the contact’s phone number is used for the display name.
All contacts with groups are ordered according to the settings on your mobile device. You can modify these settings by clicking Settings > Mail, Contacts, Calendars > Contacts > Sort order.