@feditips

I'm happy with Duo Mobile

Android:

https://play.google.com/store/apps/details?id=com.duosecurity.duomobile

Works well with PUSH notifications, too (not available w/ Mastodon, though).

If your Mastodon login is on the same device 📲 as Duo Mobile, you can have it copy the code to the clipboard 📋 , and then paste it into the Mastodon popup. 😃