This app was created as a programming exercise as well as an excuse to learn about various things I'd heard about but never worked with. Going into this, I had no knowledge of SQL, Flask, the Twitter API, Google Charts, working with databases in general, Javascript... and probably a few other things. I used the Flask guide at https://blog.pythonanywhere.com/121/ , and got the idea to use the Twitter API and Google Charts from https://www.pythonforengineers.com/build-a-twitter-analytics-app-using-python/ . Both guides were very helpful in efficiently learning about these topics, and I appreciate the "throw you into the deep end" mentality of the first few sections of the second guide.
I've hosted the app on a webpage at pythonanywhere.com: http://rtflynn.pythonanywhere.com/ . Feel free to check it out and play around with it. Pythonanywhere turned out to be a very nice tool for this project - it offers free databases and in-browser terminals and an intuitive UI for moving back and forth between the various components of a project like this.
Here's what the charts look like:
And here's what you see if you click on the 'dog' wedge of the first pie chart: