If you want to change your Username,
For Android: please tap your profile picture
> the "pencil" setting button on top right corner
> Username > confirm.
For iPhone: enter profile page> settings
> change Name> touch id for "imo" to
change name> input your username >Save.
If you can't see the new username after
changing, you may restart imo to refresh it.
Notice:
Username does not support numbers,
emojis, email address.