Why I like 80 Days (minor spoilers): so far I have circumnavigated the world in 52 days (going around the North Pole to do so—the second time I tried, the first time we all died) and in 80 days exactly. I have discovered an underground city, a robot masquerading as a person, a militant pro-tech order of nuns, and a city that walks. I have solved a murder mystery in the middle of the Pacific, punched out Jesse James, failed on multiple occasions to lead a mutiny, escaped a city under siege, and delivered a baby. I've met Otto Lidenbrock (from Journey to the Center of the Earth) but not figured out whether I can go journeying with him yet, and been given a mysterious cube of black glass but ditto.
I only wish there was a "now you've beaten the game, just go adventuring" mode, because I cannot see how anyone uses the Southern Hemisphere routes to win—I mean, you're going to and from London, that takes you considerably out of your way—and I'd love to visit Africa and South America and see what's happening there.
The author (Meg Jayanth, who wrote the incomplete Storynexus game Samsara and is British-Indian) bills it as "decolonised, multicultural steampunk," and there's a little bit more about that in this blog post. If that sounds appealing, or you'd just like half a million evocative words of AU Choose-Your-Own-Adventure very cheap, you should really check 80 Days out. (The iOS is not in the bundle, but: $5. Half a million words.)