Fintech giant Square (SQ 2.48%) posted some impressive third-quarter numbers, including more than $3 billion in revenue and a Cash App user base that has more than doubled over the past year. While the numbers were strong, the stock isn't exactly a cheap one. 

In this Fool Live video clip from our Nov. 9 "Industry Focus" show, host Jason Moser and Fool.com contributor Matt Frankel, CFP, take a closer look at Square's third quarter and what investors should keep an eye on going forward.

Jason Moser: Matt, Square, not surprisingly, reported another very impressive quarter. It was one that I felt like, after PayPal's (PYPL 0.94%) quarter earlier in the week, it seemed like Square was set up to report some good numbers and they didn't disappoint. There are a lot of numbers here that really make you feel like this business just continues to do a lot of good things, I mean, total net revenue crossed the $3 billion mark, it was up 148% if you exclude Caviar, which they sold off a while back. What stood out to you in this most recent quarter for Square?

Matt Frankel: Well, I've been following Square's brokerage efforts for a while cause I love the Cash App. Their Cash App users doubled year-over-year, which is really impressive at this stage considering how big it is. The gross profit generated by the Cash App, remember we've said a few times during the earlier stages of monetization still, the gross profit generated by the Cash App nearly tripled year-over-year. Remember they rolled out their stock trading feature on the Cash App, 2.5 million people had bought and sold stock on the Cash App as of the end of the third quarter. That's pretty impressive, I don't know the stats, but I'm sure when TD Ameritrade was invented, for example, they didn't get to 2.5 million that quick.

Jason Moser: It's a lot. They said billions of dollars have already been traded by the end of the third quarter. I saw that snippet, that was something that really stood out to me as well.

Matt Frankel: Not only is their growth impressive, but it's accelerating. Over the past 6, 7 quarters, they've grown consistently at like a 30-40% year-over-year revenue pace. Gross profit was up 63% this quarter, so not only are they still keeping their growth trajectory alive but it's going parabolic right now.

Jason Moser: It's what you want to see.

Matt Frankel: Square's quarter was pretty impressive. I bought Square a while ago, I never really envisioned it would turn into what it has, I just thought it was a really interesting payment processing platform, to be honest with you. My only problem with Square is that I didn't buy more back in 2015 or whenever the IPO was.

Jason Moser: Clearly, I've been very happy shareholder as well, and my daughters own shares, they feel pretty good about that. I can't say that I've found really anything in the quarter that concerned me, I think one thing to note, and this is not a mark against them, as a matter of fact, I think I really actually credit them for this, they're going to ramp up investments in the business next year, talking about 2021, they're talking about ramping up investments in the business around 40 percent from this year, and that will impact profitability to the extent that revenue growth is impacted. So we want to pay attention to that top-line, the investments in the business could certainly play out on profitability. Again, that seems like a short-term thing in order to ensure the longer-term success of the business. But you keep those types of things in mind because a company that's going to spend like that, who knows what the psychology in the market is going to be in 2021. Maybe that opens up a window to add to that position if the chance arises.

Matt Frankel: Yeah. For sure. I've considered pulling the trigger on some more Square for a long time, including in March when it was down in the 30s for a brief time, and then I just got cold feet. I'm learning my lesson with Square over and over that keep adding to your winners. One of these days I'll actually take my own advice and do it, when I can stop talking about it for a few days because that also has to happen.

Jason Moser: Yeah. That's one of our hurdles, but hopefully, listeners are listening and taking your advice in their consideration.