Disconnection Error with XTool iOBD2 BMW Diagnostic Tool

I bought my Xtool iOBD2 BMW diagnostic tool for iphone/ipad on shop on-line several days ago.I came across some troubles during the connection. After communicating with customer service Olivia, my problem was solved successfully. This is the dialog.

Dear Olivia:
Good morning. How are you today? I’m Dennis. I bought Xtool BMW diagnostic tool on your shop, cardiag.co.uk. I’m satisfied with the fast delivery, complete package and good price, but there is something wrong with it now.
My vehicle model is BMW X5. This is my operation process.
At the beginning, the Bluetooth connection was normal and activation was also successful.
Xtool-BMW-diagnostic-tool-1 Xtool-BMW-diagnostic-tool-2
The connection seems well, but the following error “the connection has been disconnected, please reconnect” appeared.

Xtool-BMW-diagnostic-tool-3

Then I tried other apps with the same problems. I have no idea about what to do next. Please help me!

Dear Dennis?
This is not a thorny problem.You just need to give me serial number of your device. Our engine will check which type of your diagnostic tool is, iobd2 bmw or iobd2 obd. Actually, the most important point is that you have to choose the matched app according to your device. Because you choose the fault app, your connection is failed.

iOBD2 BMW Diagnostic Tool for iPhone/iPad

iOBD2 BMW
iOBD2 BMW is one of iOBD2 code scanner series which is especially works on BMW car models. iOBD2 BMW works together with your iPhone or iPad which is IOS system, communication with your iPhone/iPad by Bluetooth/WIFI, support all BMW car models all system diagnose, support OBDII/EOBD protocol car diagnose, it not only can read car data by the application on your phone, records data like engine speed, ignition time, fuel correction, fuel consumption, coolant temperature, when you are driving the car and shows these data by form or graph format, but also can let you share your car data to social networks.
iobd2 wifi bmw diagnostic tool
iOBD2 BMW Function:
1. Support BMW car model all system diagnose, including Engine, ABS, Airbag, Transmission and so on.
2. Support OBDII/EOBD protocols car diagnose.
3. Support SI-Reset.
4. Record car data like engine speed, ignition time, fuel correction, fuel consumption, coolant temperature
5. EVAP System Test: The purpose of this service is to enable the external test equipment to control the operation of an on-board system, test or component.
6. Read vehicle info: Read vehicle info such as Vehicle Identification Number(VIN), Calibration IDs(CALID) and Calibration Verification Number (CVN).
7. Sensor test: This service is to allow access to the on-board oxygen sensor monitoring test results. The same information may be obtained by the use of [Mode 6 test].
8. Mode 6 test: This service is to allow access to the results for on-board diagnostic monitoring tests of specific components/systems that are not continuously monitored. Examples are catalyst monitoring and the evaporative system monitoring.
9. Emissions Testing: Read and clear diagnostic trouble codes. IM Readiness status