They do not. It was suggested that ones with flavour containing diacetyl could cause popcorn lung. However, cigarettes contain a lot more diacetyl, and popcorn lung is not one of the many health risks of smoking. There is some anecdotal connection between diacetyl and popcorn lung, but far from a scientific consensus.

Thanks a bunch!

Another question: What did you do with the battery? Just discard it?

Pretty darn cool! Some questions:

How did you get the placement of the standoffs correct? What did you use for standoffs? Are those screws covered in o-rings? Are those keycaps the same type as the Keychron low profile series?

Having been working on a custom 3d-printable case for my K8Pro, and one of the biggest challenges has been the exact locations of the standoffs.

Ouch… Personal phone number exposed on Google Play? Not good. If there is not a cheap and easy way for me to get a second phone number I guess I am out. Have seen it coming for a while, Google Play is no longer a place to be for indie devs.