https://devzone.nordicsemi.com/f/nordic-q-a/8491/ios-ble-scanHi All, I&#39;m using &quot;scanForPeripheralsWithServices&quot; of iOS to the BLE devices. &quot;scanForPeripheralsWithServices&quot; sometimes never return anything. I have to stop scan or turn Bluetooth off to get return from &quot;scanForPeripheralsWithServices&quot;. I donen-USTelligent Community 13Sun, 02 Aug 2015 15:16:09 GMThttps://devzone.nordicsemi.com/thread/30984?ContentTypeID=1Sun, 02 Aug 2015 15:16:09 GMT137ad170-7792-4731-bb38-c0d22fbe4515:2da025fe-5ed1-478a-a634-12a0771ea3ceBill Siever<p>A little more information may be helpful. Can you answer some of the following questions:</p> <ol> <li> <p>Do you mean the delegate&#39;s <em>centralManager:didDiscoverPeripheral:advertisementData:RSSI:</em> isn&#39;t being called?</p> </li> <li> <p>Are you sure you have the delegate object properly configured and retained (i.e., that it hasn&#39;t been released due to lack of references to it)? The Manager&#39;s delegate property is a weak reference, so you need a strong reference to it somewhere.</p> </li> <li> <p>Are you using any particular options with <em>scanForPeripheralsWithServices</em>? Or are you just calling it with <em>nil</em>?</p> </li> <li> <p>Have you tried rebooting your iOS device to ensure there isn&#39;t a quirk with the Bluetooth stack?</p> </li> <li> <p>Are you using an additional scanner App, like LightBlue? If so, the device may already be connected to a background App. Be sure all apps that may have connected to the device have been terminated before testing.</p> </li> </ol><div style="clear:both;"></div>