Best Business Card scanner app for iOS?

You don't need an app, use notes. When you scan a business card it lets you save the contact on your phone.

OneNote and Microsoft365 (assuming you use Outlook) can scan business cards and import them as a contact. However...

If you're trying to build business, you're going to have to QA *everything* that gets imported, whether it's automatic or not. Some of the fonts I've seen on biz cards are hard to decipher to begin with, let alone letting "AI" (bullshite term, IMO) guess if that is a 6 or an 8 that the camera captured while someone had the martini shakes, etc.

Just take a picture, go back to the hotel, and create the contact on a real keyboard.