I bought this while we were pursuing our 333 application. Still using it under 107, though it has a column or two that are 333 specific.
I like the idea of using digital logbook, but if ever questioned by authorities, I'd rather hand them a $9 paperback than my relatively new iPad.
I use a surveyer's notebook. It has lines on one side and graph paper on the other. I have a stock list of items that I record. Date, time, location, which batteries I used. I also record the reading from a handheld light meter, any ND filters used and camera settings. I also copy in the local Metar report and then any comments about the flights. The notebook is 5x7, bright orange and water resistant. I'm thinking about having a rubber stamp made so I could ink some standard 'fill in the blanks' on the page. And it fits nicely into one of the compartments in my hard case. Any similar sized notebook would work just as well, I just happened to have some of these already.
Actually, it's the one some drone instructor on CreativeLive uses and recommended for his commercial flights. He records his times and location as well as notes in it.
As mentioned, I rather hand them a book than a tablet or phone to see the info for a resume, or some compliance matter with authorities. I'd be more than upset if the wanted to confiscate my electronic whatever for evidence.
Oh yeah, I forgot, if you're on flytrex, it keeps a log of all your flights automatically. You can download it to pdf. Includes, date & time, aircraft, location, duration, travel distance, max distance, max ascent, max speed.