This seemed like a fun Thing, so I picked some fun apps. Specifically, the Eat This, Not That Game, and the National Archives & Records Today's Document.
First I played the Snack game on the ETNT, and discovered that yes, everything I thought was probably bad for me is actually really, really bad for me. (Honestly, I think this game is going to be uninstalled before then end of the month.)
But the second app, the one by NARA, was very interesting. The document of the day was the Marquis de Lafayette's Oath of Allegiance, signed before George Washington on June 9, 1778; it was surprisingly powerful to see de Lafayette's signature on a document that, while seen by me only in digital format, actually still exists. And then I couldn't resist checking up the document for my birth date (June 19) - it was the act (signed in 1934) to establish the national archives. Important, but decidedly less moving.
I'm not entirely certain that either of these apps will be particularly useful professionally, but they would be good for personal enrichment. (And the latter might help me with Sunday night pub trivia. And that's not nothing.)