Peripheral.m

- (void)setupService {
    // Step 1: Create CharacteristicUUID
    CBUUID *characteristicUUID = [CBUUID UUIDWithString:kCharacteristicUUID];
    CBMutableCharacteristic *characteristicM = [[CBMutableCharacteristic alloc]
                                                initWithType:characteristicUUID
                                                  properties:CBCharacteristicPropertyNotify |
                                                           CBCharacteristicPropertyRead |
                                                           CBCharacteristicPropertyWrite |
                                                           CBCharacteristicPropertyWriteWithoutResponse
                                                       value:nil
                                                  permissions:CBAttributePermissionsReadable |
                                                              CBAttributePermissionsWriteable
                                                ];
    self.characteristicM = characteristicM;

    // Step 2: Create CBMutableService
    CBUUID *serviceUUID = [CBUUID UUIDWithString:kServiceUUID];
    CBMutableService *serviceM = [[CBMutableService alloc]initWithType:serviceUUID primary:YES];
    [serviceM setCharacteristics:@[characteristicM]];

    // Step 3: Add Service to Peripheral Manager
    [self.peripheralManager addService:serviceM];
}