From http://stackoverflow.com/questions/15931227/uitextfield-set-cursor-to-start-text-position

Move cursor to beginning of UITextField

- (void)textFieldDidBeginEditing:(UITextField *)textField
{
    UITextPosition *beginning = [textField beginningOfDocument];
    [textField setSelectedTextRange:[textField textRangeFromPosition:beginning
                                                          toPosition:beginning]];
}