Investors have been laser-focused on the performance of the technology-heavy Nasdaq-100 index this year, because it hosts some of the fastest growing companies in the world. The picture hasn't been positive with the index declining 28% in 2022 (so far), placing it firmly in bear territory.

But investors who are paying extra close attention might have spotted a few technology companies delivering record results this year, even in the face of broader economic challenges. Their respective share prices might still be beaten down, but that spells opportunity, especially going into the new year.

Uber Technologies (UBER -7.64%) and Duolingo (DUOL -3.39%) are two of them, and here's why investors should consider buying them before they rebound. 

1. Uber's mobility business has roared back to life

Uber's bread and butter has always been mobility (ride-hailing), but the company has never been scared to conquer new verticals. Its Uber Eats food-delivery platform is now one of the largest in the world, and it carried the entire company through the pandemic as social restrictions destroyed demand for mobility services. And now, its Uber Freight platform is growing like a weed with significant long-term promise.

Let's begin there, because in the third quarter, Uber's freight segment grew a mind-boggling 336%. Not so long ago, it was an inconsequential contributor to the company's overall financial results, but it just generated $1.8 billion in quarterly revenue following Uber's acquisition of Transplace in Nov. 2021. Uber says the platform now has over 200,000 users and manages $17 billion in freight, making it one of the largest logistics networks in the world already.

But the headline in the third quarter was mobility, because the segment continued its resurgence back to the top spot as Uber's largest driver of revenue. Revenue came in at $3.8 billion with a little help from an accounting adjustment relating to its operations in the United Kingdom. But its gross bookings (the amount of money customers spent on the service) came in level with food delivery at $13.7 billion. 

Its bookings growth rate, however, was 45% compared to delivery's 13%, suggesting mobility could already be the dominant driver of bookings in the current quarter.

Uber now has a record-high 124 million customers across all of its platforms, which was a 14% year-over-year increase. But the company says mobility customers specifically grew 22%, highlighting a return to normal now that most pandemic restrictions have been lifted.

Uber stock is down 36% in 2022. But its business is very much on the upswing, and investors might view that disparity as an opportunity to buy. Some of the pressures on the broader economy like inflation, appear to have peaked, so the new year could be more favorable to tech stocks like Uber. 

2. Duolingo has more paying users than ever

Duolingo estimates there are 1.8 billion people learning foreign languages across the globe. As of the third quarter, its platform attracted 56.5 million monthly active users, making it one of the largest providers in the world, yet it still clearly has an enormous runway for growth.

What's the key to Duolingo's success? It has a mobile-first approach, and it has gamified the learning experience to make it fun, interactive, and even social, allowing users to connect with friends and family in-app. The company has delivered such a strong product that a rapidly growing number of active users are paying to unlock additional features to take their education one step further.

In the third quarter, Duolingo had a record-high 3.7 million paying subscribers, up 68% year over year. It drove the company's revenue 51% higher to $96.1 million, marking its fastest growth rate of the year despite the weakening economy. Duolingo continues to be the highest-grossing app in the education category across both the Apple's App Store and Alphabet's Google Play Store.

But there could be plenty of financial growth left in the tank. There's a clear shift toward digital when it comes to language education, and Duolingo expects that segment of the market will grow more than twice as fast as nondigital until at least 2025. The opportunity by then could be worth $47 billion annually.

Duolingo stock has also declined 36% year to date, and like Uber, its business is still firing on all cylinders. The company has proved its ability to deliver even in tough conditions, and its runway for growth makes it a great long-term buy here while the stock is trading at a discount.