It's way easier to do both of those things on an Apple Watch.
Starbucks POS's accept Apple Pay; invoking it on the Watch is really easy (double tap the side button; hold near screen). Authy 2FA works well on the Watch as well; app-based 2FA like LastPass Authenticator and Okta work EXTREMELY well on it (better than the Pebble, at least on iOS). Google app 2FA sucks on iOS; I'm assuming it's better on Android.
On the Apple Watch it's a chore, but as a fashion accessory it's no comparison.
Plus both my pebbles developed screen issues, shame Apple drank their milkshake.