Great app with great support.
There are a lot of apps for turning contacts into QR codes, but this app is particularly nice because it provides both Home Screen and Notification Center widgets, works on a paired iPhone and Apple Watch, and lets people scan your business card easily from your Apple Watch. Note: cards don't sync with the iPad or macOS, but are available there too. The app also allows multiple cards for a small in-app payment. If you give out different information for work, social events, or side jobs, this is a surprisingly useful feature that I now consider essential. Best of all, the cards aren't tied to your Apple contacts or your "Me" card, so you can trim extraneous information or add additional details that you might need on a business card without having to modify your native contact card. Other apps I've tried don't offer that flexibility. The developer is also very responsive. He quickly resolved a problem caused by undocumented changes in WatchOS that created iPhone to Watch sync problems when editing cards. I highly recommend this app!