I'm developing an iOS application that relies on peer-to-peer discovery and connection using Bluetooth. The expected behavior is: Two iOS devices with the application installed. Both users marked as "visible". When within Bluetooth range, the devices should discover each other and establish a connection. However, the problem occurs when: The application is in the background (minimized) OR The device is locked (screen off). In these states: The devices can no longer be detected. The search returns no nearby devices. Connection could not be established. ChatGPT: What you want to do probably runs into a structural limitation of iOS — it's not a bug. And iOS: severely limits background BLE scanning. reduces advertising frequency. may even stop completely depending on the state (lock screen). In other words: 👉 iPhone was not designed to function as a "continuous radar" between background apps. Apps that do something similar (like AirDrop or Find My): use Apple's private or privileged APIs or combine BLE + Wi-Fi + Ultra Broadband. i need help : /

I have an app that uses BLE to connect to access doors. Since iOS 26, when it hasn't connected to any doors for a while, it deactivates, whereas in older versions of iOS it continues to work all day without stopping. Has anyone else experienced this? I've found problems with people who have had the same issue since upgrading to the latest version of iOS 26. Is there a known issue with BLE in iOS 26? I haven't found any official information. thnks

When my Bluetooth peripheral device has both HID and MIDI services, the iOS Bluetooth host repeatedly sends different "Control Opcode: LL_CONNECTION_UPDATE_IND" to the peripheral, updating approximately every 100ms. The Bluetooth peripheral cannot handle such high-frequency update requests and typically disconnects with an error 0x28. My Bluetooth device uses the NRF52832 chip, and I have communicated with NORDIC and replicated this issue. This problem only occurs on iOS 26; it does not happen on earlier versions. I think it might be caused by the HID service in iOS requesting faster connection parameters for low latency, which then gets erroneously reverted for an unknown reason, leading to repeated competition and entering into a deadlock. Here is the communication record with NORDIC: https://devzone.nordicsemi.com/f/nordic-q-a/124994/ios-26-bluetooth-disconnect-issues This is the screenshot captured using the Bluetooth sniffer:

I am using a Raspberry Pi 5 (BLE 5.0) to read sensor data and send it via D-Bus and BlueZ to a Flutter application (flutter_blue_plus) for both iOS and Android. The goal is to display these real-time sensor updates directly on the device. On Android, the data transmission is immediate and the real-time visualization is extremely smooth and fast. However, on iOS, both BLE write and notification commands appear with noticeable latency—not only in real-time displays, but also when comparing ordinary notification feedback between the Raspberry Pi terminal and the iOS app. It seems that iOS buffers several BLE packets internally and then dispatches them in batches, which always introduces an additional delay. Additional setup details: I sample and transmit data every 25ms, sending binary packets of 20 bytes (length shouldn’t be a limiting factor). On the iOS side I am using an iPhone 15 Pro with iOS 18.6.2 (BLE 5.3). The Raspberry Pi (using btmon for logging) confirms after connection setup that the connection interval is fixed at 30ms (and cannot be changed). I have tried sending BLE packets every 30ms so that exactly one packet arrives per interval, but this made no difference—the latency and batch delivery remain. Interestingly, faster transmission rates (e.g. sending every 10ms) make the real-time display look smoother on iOS, but the guaranteed overall system latency does not improve. Also these methods used: write-without-response, using app in release modus (no debugging) Is there anyone familiar with this problem or a potential solution? Or is iOS simply not optimized for true real-time BLE data streaming and visualization? Any pointers, technical insights or workarounds would be greatly appreciated.

Hello. In my app, I need to implement the following mechanism: I need to collect data from nearby Bluetooth devices, process them, and send this information to the server at short intervals, including when the app is minimized. Is this possible on iOS? BGProcessingTask has restrictions related to battery saving policies and does not guarantee task execution at specific intervals. Additionally, there is a limitation on background task execution, which can occur no more frequently than every 15 minutes. However, some apps, such as Google Maps, work in the background and update geolocation data. Could you suggest a solution for this task? Thanks for any help on this topic

Hello, Our device firmware has a companion iOS app that allows a user to rename it. We are connected to the iPhone via BT Classic. The new name is reflected on the app, however, the iPhone BT device list still shows the old name. It doesn't seem to get updated to the new name unless we unpair/re-pair the device to the phone. Is there a way to get the iPhone to update to the new name in the Settings BT device list without unpairing the device? Is this possible in BT Classic? Thanks.

Hi, I want to develop an application with service can discover neighbors devices bluetooth in background, this service can run even app was killed. The scan of bluetooth start every 5 sec as service, and find Bluetooth device and can read data from BLE device. It's possible with IOS? any limitations? Thank you Regads, Thuyet

Hi, we actually have an application where we use iPad to run a WEB Application to display multiple Entertainment/Information content and control Infrastructure. The device is usually connected to a base station (own design) using BLE und USB only for power, is locked in single App Mode using MDM. As long as the App is open it is working fine. But now we like to go to the next step and like to have the device movable and use power save. How can we achieve the iPad wakes up immediately from sleep mode (directly to the app) if somebody is pressing a button on the base station (we support Comm Port, and HID Keyboard service, we can change code on base station if needed). And how can we achieve the same over Network (Wi-Fi or Ethernet with Adapter, Internet access is not always available). May set a state on the MQTT broker and tablet should wake up from sleep. Thanks for feedback Patrik

We have observed a significant increase in download time from the sensors to the mobile device after recent OS updates. We are connected to the external sensors via the BLE interface using the following connection parameters(15,15,0,6000) https://mbientlab.com/tutorials/MetaMotionRL.html: example 1.For 1 Meter with duration of 28 Seconds the IOS 17.1 taking 44 secs where as IOS 17.5.1 taking 82 secs . 2..For 1 Meter with duration of 45 Seconds the IOS 17.1 taking 74 secs where as IOS 17.5.1 taking 143 secs . Even with the same connection parameters, download times were considerably lower in iOS 15 and below devices. We are currently using the connection parameters 15, 15, 0, 6000. I have learned from some documents that the minimum connection interval was changed to 20, but when I tried it, the download time increased further. I am seeking assistance on how to achieve the same download times as the older versions. https://mbientlab.com/community/discussion/comment/11852#Comment_11852

Hi, Is it technically possible to stream external BT device's microphone input to iPhones speakers output?

let session = AVAudioSession.sharedInstance() do { try session.setCategory(AVAudioSession.Category.playback) try session.setActive(true) //playAndRecord <AVAudioSessionPortDescription: 0x2828dc2b0, type = Speaker; name = 扬声器; UID = Speaker; selectedDataSource = (null)> //playback <AVAudioSessionPortDescription: 0x28204c1a0, type = BluetoothA2DPOutput; name = M2; UID = 00:02:5C:22:22:11-tacl; selectedDataSource = (null)> print(session.currentRoute.outputs) } catch { print(error) } when I ssession.setCategory(AVAudioSession.Category.playback) audio play output a2dp ble devices. session.currentRoute.outputs print bellow `<AVAudioSessionPortDescription: 0x28204c1a0, type = BluetoothA2DPOutput; name = M2; UID = 00:02:5C:22:22:11-tacl; selectedDataSource = (null)> when I ssession.setCategory(AVAudioSession.Category.playAndRecord) output <AVAudioSessionPortDescription: 0x2828dc2b0, type = Speaker; name = 扬声器; UID = Speaker; selectedDataSource = (null)> BluetoothA2DPOutput is gone. but it is normal in ios15-16. Is there any solution? I want to record audio and play music at the same time. And the music is output from the Bluetooth speaker

I saw a similar post to this where the issue was fixed in the final iOS17 release, but I am still having a problem since my situation is slightly different. I am wondering if its a bug based on current behavior, but was hoping maybe someone knows if the issue is with my setup? I am trying to monitor an external USB camera's audio input using the new iOS17 external call for iPad, over bluetooth. func setupAudioSession() { let audioSession = AVAudioSession.sharedInstance() do { try audioSession.setCategory(.playAndRecord, mode: .default, options: [.allowBluetoothA2DP, .defaultToSpeaker] ) try audioSession.setActive(true) } catch { print("Failed to set up audio session: \(error)") } } When my execution order is: setupAudioSession() // code above // discover and connect the session AV inputs to the external USB // start an audio engine // connect audio engine output to a buffer queue and play // start the session My app does not allow routing to the headphones and directly switches to speaker. However if I change the order to this: setupAudioSession() // code above // discover and connect the session AV inputs to the external USB // start an audio engine // start the session --- !starting before connecting output! // connect audio engine output to a buffer queue and play The session stays connected to Bluetooth and plays over the headphones. However if I suspend the app and relaunch, I get switched back to speaker. I understand maybe the system is trying to prevent an audio feedback loop? But don't understand why launching the session early would get the desired behavior. Any help would be greatly appreciated.

Hello all, I am interested in trying to develop a short-medium range (>100 meters) tracking device for a hobby project in order to gain some literacy in mobile phone software, and have a few questions. I am new to working with anything iOS so please correct me in any mistakes I make in this query. Is RFID or Bluetooth better for tracking and implementation on iOS? How difficult is device implementation into iOS and apps such as find my iPhone? How would one go about it? If I wanted a tracking device to send notifications based on location/distance from another device, could I do that with Apples framework or would I have to create my own app? What programming language would be used in this sort of endeavor? Would C++ work or does iOS use different ones? Thanks in advance, any and all advice is greatly appreciated.

Hello everyone, sorry for my ignorance about it, with ANCS I managed to get all the notifications except the alarm that rings and the timer expired, where am I wrong? do they travel on other channels like gatt? if yes can someone help me understand how to receive these 2 information? the alarm goes off and the timer expired? Thanks in advance to everyone who will help me, Marco.

Hello, Our application is a health application that functions alongside a device transferring data via Bluetooth. There is continuous data transfer happening from this device. However, when operated on an iOS device, the application gets cut off in the background after a certain duration, negatively impacting the user experience. As is known, the background services of an application being terminated after a certain period is generally associated with how iOS manages system resources. In our case as well, we came across this issue before we implemented a formatted background task. Therefore, to address this situation, we used a formatted background task in our application, but the problem still persists. Unable to resolve the issue, we decided to analyze how other Bluetooth devices work on iOS devices. For example, when an electronic watch is connected, the Bluetooth connection never gets cut off. However, why can't we achieve the same performance with our device? I would be extremely grateful if you could shed technical insight on this matter and share your experiences. Furthermore, if you have any recommendations on how to handle such situations, I would love to hear all about them. Thanks in advance for your help.

I'm currently developing an app that requires detecting Bluetooth connections and disconnections in cars. During testing, I've observed the following behavior: In certain vehicles, only a Bluetooth connection via the car's hands-free system is available. In these cases, the device initiates a call to itself, which is then displayed on the vehicle's infotainment system. In some of the tested vehicles, this self-call is brief and only occurs during the device's connection or disconnection process. However, in other vehicles, the self-call remains visible throughout the entire duration of the device's pairing with the car's Bluetooth system. This blocked call blocks the entire infotainment system and causes the connection/disconnection observers in my app to stop functioning as expected. I'm looking for a solution or preventative measures to address this issue. Any guidance would be greatly appreciated. Here is a snippet of my code: `func audioSessionSetup() { do { resetAudioSession() let audioOptions: AVAudioSession.CategoryOptions = [.duckOthers, .allowBluetooth, .defaultToSpeaker] try audioSession.setCategory(.playAndRecord, mode: .spokenAudio, options: audioOptions) registerNotifications() try audioSession.setActive(true) print("audioSession is active") } catch let error as NSError { print("Failed to set the audio audioSession category and mode: \(error.localizedDescription)") } } /// Reset the audio session to deactivate it. func resetAudioSession() { do { try audioSession.setActive(false, options: .notifyOthersOnDeactivation) } catch let error as NSError { print("Failed to reset the audio audioSession, error: \(error.localizedDescription)") } } @objc func handleRouteChange(_ notification: Notification) { guard let userInfo = notification.userInfo, let reasonValue = userInfo[AVAudioSessionRouteChangeReasonKey] as? UInt, let reason = AVAudioSession.RouteChangeReason(rawValue: reasonValue) else { return } switch reason { case .newDeviceAvailable: /// Handle new device connection print("New device connected.") checkConnectionForSelectedOutput(notification) case .oldDeviceUnavailable: /// Handle device disconnection print("Device disconnected.") handleLocationServices(state: false) default: print("break") handleCategoryChange(notification) break } } private func handleCategoryChange(_ notification: Notification) { if let connectedDeviceName = getConnectedBluetoothDeviceName() { if connectedDeviceName != connectedDevice && connectedDeviceName == BluetoothUtils.getBluetoothInfo().portName { connectedDevice = connectedDeviceName checkConnectionForSelectedOutput(notification) } } else { audioSessionSetup() checkConnectionForSelectedOutput(notification) print("handleRouteChange audio session is active") } }`

I'm trying to determine if Core Bluetooth, in the latest versions of iOS and iPadOS, supports scanning for periodic advertisements as defined in Bluetooth 5? If so, what configuration parameters are required for a peripheral device to successfully achieve recognizable periodic advertisements that will be discovered by iPhones/iPads? For instance, supported PHY settings or anything else? If iOS/iPadOs doesn’t support periodic advertising, is it on the roadmap? If so, when will it be available and which devices will be supported? Thanks.

Prior to IOS 14 this functioned well with multiple types of devices (JBL speakers, headsets, computer) on both our iPhones. Now, and with having tried all the recommended fixes, they no longer discover these. The iPhone may discover each other but the connection fails. Does connect to AirPods but now always needing pairing and with many fails before. It's a useful feature and a deal breaker for my next choice of personal device so, let me know how soon this can be resolved. The response clock is ticking.

is it possible to change from Bluetooth to iPhone speaker in iOS 14? All I want is real-time control of where the audio comes from

Greetings all :) We have a third party device designed to be paired with multiple iPads. It's designed for a class room setting, where all student will have their own iPad, and each student will have access to any number of third party bluetooth enabled devices. The device currently has a baked in limit of x5 devices being paired to it at any one time. This means for up to 5 'lessons / classes' everyone can pair with any device without issue. However on the sixth lesson, connecting to the bluetooth device then fails, and the only fix is to go into the Settings, unpair any previous connected bluetooth devices, and then start the process again. Is there any workaround to allow either 'disconnecting' or 'forgetting' devices (in the same session on the same device) to allow re-pairing? At present it is a really poor user experience expecting all users to 'forget' all bluetooth devices, before being able to continue. All help / advice much appreciated.