>Installing an app not from the appstore is almost impossible for a non-savvy user.

I would post a video demonstrating step-by-step how to install non-approved apps in Chrome. Download the app. Open chrome://extensions. Tick Developer mode. Drag the app from your Download folder to the extensions page. Enjoy those nicely summarized ratings!

Actually, here are two existing videos on the subject:

https://www.youtube.com/watch?v=sf9mthhfzpY

https://www.youtube.com/watch?v=hVj_FJwI2Rw

Hopefully, if a user is savvy enough to get into Yale, those instructions would suffice.