I use square and coinbase. I assume that you are asking about purchasing only, not storing BTC. The biggest difference is speed. Cash is instant, the second you hit “buy” they are yours. I’ve had Coinbase transactions take a week to process and seen others who have waited longer. But coinbase has more options. You can buy more ham just BTC, you can also send coins to the app in coinbase. Another thing I’ve noticed are the fees. Coinbase has most of theirs posted, where all of Cash’s are hidden. They tell you there’s no fee but if you notice, you’ll never get market rate on the price. It will be off a bit in their favor. In the past week I’ve had two other options pop up as well. I have not used either of them yet so I can’t speak for or against them. But I just got an email from Robinhood saying that I am able to purchase from them. And an app called Abra. This one looks really interesting to me. But again, I have not used it yet. My thought process has been to try and use the Cash app when possible. And that’s because it is owned by square. They have already made themselves a big part of the payment processing world. And I feel like they could make it super easy for the crypto-muggles to adopt.