Lately I’ve been playing more Sudoku on my train commutes (also about 40 minutes). If you want to look at a screen less, you could get a book of Sudoku puzzles or crosswords or word searches. I feel like it helps me keep my brain sharp
For me it’s NYT connections, wordle, mini. Knotwords mini, classic, twist. Puzzmo crossword. Wall Street crossword(s). I will happily add more if you have good suggestions.
I like to have one book to make me think and one for fun. At the moment I’m reading the Fall by Albert Camus and Pageboy by Elliot Page. Both are insightful but when I get tired of first person pov and need more academia I can swap!