iPhone 7, baby!
That's old but still IP67 water resistant! I'm surprised it still works - I find iPhones last about 2 years and then the battery goes to sh_t: My 2019 iPhone 11Pro battery is starting to not last a full day... right on schedule. Luckily, my iPhones have been company-supplied or I'd be ticked off at the actual useful life.
Back to the topic at hand, I do like the cover art on these new logbooks!