The most-anticipated number released recently for Apple (NASDAQ:AAPL) followers told us how many iPhone 6's they sold over the weekend. A record 10 million units.

The iPhone 6 Plus let loose into the wild. Photo: Flickr user William Hook

Considering there were over four million preorders for iPhone 6 and the big-screen 6 Plus within the first 24 hours of their unveiling -- far surpassing those received for the 4s and 5 -- and the event saw people once again sleeping out of doors and around the block to be among the first to get one, it's not surprising the number they finally tallied smashed all previous records.

But for kiosk operator Outerwall (NASDAQ:OUTR), a bigger question might be what are all those people going to do with their old phones?

Dialing for dollars
Smartphone users have the option of turning in their old device to where they bought their phone originally, such as at Best Buy (NYSE:BBY), Target (NYSE:TGT), Apple, or the various stand-alone stores from the carriers themselves, and get a credit toward a new one. The introduction of the iPhone 6 is likely going to be one of the biggest motivators to get consumers to upgrade.

Yet they also have the option of heading to an Outerwall kiosk and getting cold, hard cash for their old phone, which depending upon how quickly they act could be worth more than their credit.

Not exactly money for nothing: upgrade for cash. Image: Outerwall

Approaching terminal velocity
According to uSell, an online gadget marketplace rival to Outerwall's ecoATM kiosk service, prices received for old iPhones begin dropping by as much as 11% within two weeks of a new model's introduction, while almost two months after they hit the market older models lose 21% of their value.

Right now, with the iPhone 6 just out, you can sell your old 64GB 5s with Verizon (NYSE:VZ) for almost $280 on uSell or Gazelle, yet another electronic gadget market. Yet if you wait a few weeks before acting, the Verizon price might fall to $225 or lower. The same phone with Sprint goes for just $145 on uSell, but $180 on Gazelle. Obviously shopping around for the best deal pays.

While services like uSell and Gazelle have been around for awhile, Outerwall is trying to make the kiosk model just as powerful as it was for its Redbox movie rentals and its green Coinstar coin exchanges.

Seaching the outer reaches for a business model
Outerwall bought ecoATM in July 2013, and though it has a long way to go before it reaches the ubiquity of the 44,000 or so Redbox kiosks, it expects to have 1,100 units installed by the end of the year.

Even so, the rollout of its kiosks hasn't been nearly as smooth as it anticipated and it admits negotiations with malls -- the prime locations for the smartphone trade-in boxes -- has been more difficult than it thought it would be. Which is part of the reason why many analysts aren't sure if ecoATM can be much of a big moneymaker for the kiosk operator.

Outerwall tries out a lot of new ideas. Redbox has been its cash cow to date, but even it realizes the days of the DVD rental are dwindling, hence its move into streaming video. It's also tested out services like consumer electronics kiosk Orango, coffee kiosk Rubi, prepared-food kiosk Crisp Market, and interactive photo-booth Star Studio, though all have failed and were primarily responsible for the 7% decline in operating income in 2013. All have since been discontinued.

EcoATM accounts for only about 4% of total revenues last quarter, or $23.8 million, so it's not going to change the dynamic of Outerwall's business anytime soon, and it would need to double in size to even start reaching the point where it could impact operations.

The apple of its eye
Which is why the new Apple smartphone will be key to determining whether this new venture will be any more successful than those it tried out before.

According to the folks at AppleInsider, trade-in site Gazelle reported consumers dumping their older phones for cash surged 293% following the iPhone 6's debut.

But that also means there's lots of competition for Outerwall. While its ecoATM seems to have an advantage over its online rivals because it pays out cash immediately versus having to mail in your device and wait for payment, it still runs up against the bricks-and-mortar stores giving you a credit toward the purchase of the new phone.

It's not just older iPhones people want to get ride of, but Samsung devices, too. Photo: Flickr user Karlis Dambrans

The kiosks locations in malls suggests they'll be more of a spur of the moment, impulse decision whereas a trade in at Best Buy or the Apple store would seem to be more of a planned destination. Still, if Outerwall gets more kiosks into more spots, they could become destinations in and of themselves.

Rotten to the core?
In the end, Outerwall missed an opportunity with the iPhone 6. Had it had more kiosks in place it might have been able to capitalize on the frenzy for the Apple smartphone. No doubt its kiosks that were in place probably did a brisk business, now it remains to be seen just how many phones were turned in, and whether Samsung can generate as much excitement with its next iteration of its Galaxy device.

By then, investors will be able to figure out whether the ecoATM is worth the investment Outerwall made in it. 

Rich Duprey has no position in any stocks mentioned. The Motley Fool recommends Apple. The Motley Fool owns shares of Apple. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.