self.bleManager = [BLEManager sharedInstance];

// Set scan timeout to 10 sec, only available when `continousScan` = NO
self.bleManager.scanInterval = 10;

// Scan will not terminate until user invoke `stopScan`
self.bleManager.continousScan = YES;

// Set connect timeout to 10 sec
self.bleManager.connectTimeout = 10;

// Set enumeration timeout to 10 sec
self.bleManager.enumerateTimeout = 10;

// Set write characteristic value timeout to 10 sec
self.bleManager.sendDataTimeout = 10;

[_bleManager scanPeripheralWithUUIDs:uuids resultCallback:^(NSDictionary<NSUUID *, BLEPeripheral *> *devices, NSError *error) {
    NSMutableArray *devs = [NSMutableArray array];
    [devices enumerateKeysAndObjectsUsingBlock:^(id  _Nonnull key, id  _Nonnull obj, BOOL * _Nonnull stop) {
        NSLog(@"Device UUID: @%", key);
        BLEPeripheral *device = obj;
        // Do anything you need with BLEPeripheral
    }];
}];

[_bleManager connectPeripheral:peripheral completion:^(NSNumber *success, NSError *error) {
    if (error) {
        NSLog(@"Failed to connect BLE Peripheral");
    } else {
        // Connected
        Do everything you need after connected
    }
}];

_bleManager.connectedPeripherals

// Subscribe
[_bleManager subscribeNotificationForPeripheral:peripheral
                             characteristicUUID:BLE_CHARACTERISTIC_UUID   // Characteristic UUID String, eg. FFE1
                                 resultCallback:^(NSData *data, NSError *error) {
                                    if (error) {
                                        NSLog(@"Error: %@", error.localizedDescription);
                                    } else {
                                        // Processing `data` as you want
                                    }
                                 }];
                                 
// Unsubscribe
[_bleManager unsubscribeNotificationForPeripheral:peripheral
                                forCharacteristic:characteristic];

[_bleManager readPeripheral:peripheral withCharacteristic:characteristic completion:^(NSData *data, NSError *error) {
    // Error is not null if read fail
}];

[_bleManager sendData:data
 toPeripheral:peripheral
 characteristicUUID:characteristicUUID
 completion:^(NSNumber *success, NSError *error) {
    // error indicate the write operation is success or not
 }];

[_bleManager disconnectPeripheral:peripheral
                       completion:^(NSNumber *success, NSError *error) {
                            // Indicate disconnect or not
                       };

/// Disconnect notification
extern NSString *BLENotificationDisconnected;

/// Scan stop notification
extern NSString *BLENotificationScanStopped;