I have used excel in the past, RF generation, as well as a variety of apps. The one I ended up choosing is
https://www.collectorz.com/game and using their android app (CLZ Games). It is a $15 purchase, but I love it. It categories everything nicely, has barcode scanner, lists whether I have a game CIB, loose, manual only, etc. It took some getting used to, but I love it. They have a free trial where you can list like 20 games or so and get a feel for it. I liked the app so much I bought the movies app as well.
Admittedly, I tried the book and comic book versions - not a fan. But the game one is their bread and butter and they have pretty regular updates.