I have used Bluetherm SDK (http://www.thermoworks.com/products/logger/bluetherm_bluetooth_probe.html) in my iOS APP. But the Application has been rejected by the Apple
Reasons
Not in MFI Program ----- MFi - Program Authorization -----
We are unable to post your app to the App Store at this time because your app has not been authorized by the accessory manufacturer to work with the MFi accessory. Please contact the accessory manufacturer to request your app be added to the MFi Product Plan form.
Once the accessory manufacturer confirms that your app has been added to the MFi Product Plan form, please reply to this message. When we receive your reply with this confirmation, we can proceed with the review; we do not require a new binary even though your application state in iTunes Connect state is Rejected.
If you have not yet provided the accessory's MFi Product Plan ID (PPID), please enter this information in the Notes section for your app in iTunes Connect. If you do not know the PPID, please request this information from the accessory manufacturer.
Please suggest to move ahead.
Thanks in advance.
The Apple message seems pretty clear - While the Bluetherm accessory is MFi certified, your app is not listed on the Bluetherm product plan as an approved app to work with that accessory.
From the ThermoWorks web page
So, my guess is you need to email or call this person and ask them to list your app on the Product Plan Form for the device.