ios - Iphone detecting bluetooth devices -

i doing iphone app , need nearby bluetooth devices. i'm using corebluetooth framework , doesn't work. know framework low energy bluetooth, bought bluetooth 4.0 usb adapter support low-energy. i'm testing app in iphone 5. code

- (void)centralmanagerdidupdatestate:(cbcentralmanager *)central{  nsstring *messtoshow;  switch (central.state) {     case cbcentralmanagerstateunknown:     {         messtoshow=[nsstring stringwithformat:@"state unknown, update imminent."];         break;     }     case cbcentralmanagerstateresetting:     {         messtoshow=[nsstring stringwithformat:@"the connection system service momentarily lost, update imminent."];         break;          }     case cbcentralmanagerstateunsupported:          {         messtoshow=[nsstring stringwithformat:@"the platform doesn't support bluetooth low energy"];         break;          }     case cbcentralmanagerstateunauthorized:          {         messtoshow=[nsstring stringwithformat:@"the app not authorized use bluetooth low energy"];         break;          }     case cbcentralmanagerstatepoweredoff:          {         messtoshow=[nsstring stringwithformat:@"bluetooth powered off."];         break;          }     case cbcentralmanagerstatepoweredon:          {         messtoshow=[nsstring stringwithformat:@"bluetooth powered on , available use."];         [mgr scanforperipheralswithservices:[nsarray arraywithobject:[cbuuid uuidwithstring:@"180a"]] options:[nsdictionary dictionarywithobject:[nsnumber numberwithbool:no] forkey:cbcentralmanagerscanoptionallowduplicateskey]];          [mgr retrieveconnectedperipherals];           break;     }                } nslog(messtoshow);  }     - (void)centralmanager:(cbcentralmanager *)central diddiscoverperipheral: (cbperipheral *)peripheral advertisementdata:(nsdictionary *)advertisementdata rssi:(nsnumber *)rssi { nslog(@"did discover peripheral. peripheral: %@ rssi: %@, uuid: %@ advertisementdata: %@ ", peripheral, rssi, peripheral.uuid, advertisementdata); [mgr retrieveperipherals:[nsarray arraywithobject:(id)peripheral.uuid]]; }  -(void)centralmanager:(cbcentralmanager *)central didretrieveperipherals:(nsarray *)peripherals{ nslog(@"this it!"); } 

this print "bluetooth powered on , available use.", doesn't find usb bluetooth or other nearby bluetooth device. need solution this, im getting crazy. thank much.

are sure 180a right service?

if not try:

[mgr scanforperipheralswithservices:nil options:[nsdictionary dictionarywithobject:[nsnumber numberwithbool:no] forkey:cbcentralmanagerscanoptionallowduplicateskey]];