While I am not well versed in understanding the rationale of the FDA for determining the PMOA of a device, in this particular case i believe that it is a device. The rationale being that the drug component of the device has already been tested and approved by the FDA and is currently being used to treat patients. The innovative aspect of the device that requires further investigation and validation is the device/monitoring aspect of the product. This becomes increasingly important as patients will be relying on the application to determine when to take their next dose. The risks being too late and the drug wears off or too soon and you have an overdose. The determining factor for a majority of the newly introduced risk lies with the device component of the product.
Another thing to not is that since medical information is being collected and potentially transmitted, HIPPA regulations will apply as well and must be followed before the device can be actually be put on the market.
Now this is a question, I have for you all, does FDA approval mean that the device can now be put on the market or does that only cover the aspects of the device which are regulated by the FDA? In this case patient information.