I find that my phone is already in my hand half the time when I go to the subway, and the other half the time it's easier to fish my phone out of my pocket than to get out my wallet and pull out the correct credit card. But it's a matter of what works best for you. And if you only have one RFID credit card in your wallet, you might be able to just tap your whole wallet without having to fish out an individual card (like most FTers, I have at least a half dozen different cards with RFIDs in my wallet, so that would never work for me). Regardless, OMNY is MUCH easier to use than a Metrocard. It's amazing how quickly it reads ApplePay!

Note that OMNY is able to distinguish separate payment devices even when using the same credit card account. mrsmicah and I both have the same card saved on our phones for use with subway rides, and when I log into OMNY and look up that card number, it shows two separate "devices" (and therefore tracks the weekly cap separately for the two of us) under the heading of that card number. It seems to be an all-around very well designed system, which is unusual for an MTA deployment!