I quite like Turbolinks too, but it can have some unintended interactions with other JS code. If you're looking to make your non-SPA site faster another way, you can try https://instant.page/ as well. It preloads pages as you hover over them, which makes links feel like they load instantaneously. It's a pretty cool trick! You can try it out on their project website or on https://www.snazz.xyz.

Curious if you (or anyone else) have used the ios and/or Android adapter for mobile? Seems like the repos are getting stale.

Getting SPAness on web and mobile apps for free would be the holy grail. Basecamp claims it works great for their mobile app.