A new key is generated every year for Vernier titles that are subscription-based. We do this in order to balance two competing needs: we want to make it very easy for you to share the apps with your students, yet we want those easily-distributed links to eventually expire if they get outside of your school in order to protect Vernier’s intellectual property. If you had an unchanging access code, then any codes that leak outside your school would also be valid indefinitely.
Note that once a student has accessed Video Analysis on their device, the full URL is not needed. Browsing to videoanalysis.app is enough to re-enter VA.
Simply using an app while online once every four weeks will renew its license, and a user will not need to enter an access code again until it expires.
Tip: There are two custom information fields in the About dialog of the apps. You will see the expiration date of the license, and you will see the name of the school associated with that access code.