1. Leverage an existing nicotine delivery system rather than create a new delivery system which would require very significant additional development effort followed by an FDA approval process.  (Not to mention the need to manage logistics of sourcing and supplying the consumables!)

2. Create an "arms length" interface with the existing delivery system.  Hacking, tampering or otherwise modifying the existing nicotine delivery system will violate the integrity of the FDA approved nicotine delivery system.

3. Device will operate on an interrupt basis to conserve battery power.  All central processing and radio communications will be shut down when idle.

4. Keep the device as simple as possible to keep the cost down.

5. Leverage smartphone ubiquity as the primary interface for usage analytics and reduction guidance.

6. Leverage cloud computing for archival data storage, research and machine learning development.

The only available "arms length" integration available to the JUUL (other than trying to interface with the apparent USB port on the bottom which is presumably proprietary since I could find no spec on it) is to read JUUL status from the LED indicator LED.  Here is what I could gather from grocking the web.

There are two state flow diagrams, Operational Flow and Set-up.