New words are being created daily in various areas of life. Your kids start using new words, the marketing people do the same, as do the chemical engineers, etc.
A subscription where you select areas of interest and the degree to which you are interested in new words (from when they just start appearing on the scene to only if they are de facto standard.) Based on these you will get alerts when new words are discovered.
Using positive words helps your brain develop, while negative words increase your stress hormone (according to some research.)
An app running on your smartphone that listens to you and analyzes the words you use. When your use of negative words goes above a certain threshold you set, the app will alert you.
To find out how much you write – you might want to start writing more if you see you output, maybe start the novel you’re always dreaming of.
Install software on all devices and aggregate the data online.