2016 has been brutal for Yelp (YELP -0.30%) investors. Shares of the local reviews giant have fallen more than 30% since the beginning of the year. Part of that decline was fueled by the release of the company's fourth-quarter earnings earlier this month. Although Yelp exceeded analysts' expectations, its future is looking increasingly unclear.

During the company's subsequent earnings call, CEO Jeremy Stoppelman, CFO Rob Krolik, and COO Geoff Donaker spoke about the trends currently affecting the business and their outlook for the future. Here are five of the most important quotes from that call (transcript provided by Thomson Reuters).

Ramping up marketing to boost smartphone penetration
Over the last few years, Yelp has shifted its focus from its website to its app. Users of Yelp's app are more engaged, and the company can target would-be buyers more effectively. Yelp has managed to rack up about 20 million average monthly app visitors, but there are still millions more smartphone users that could be enticed to make use of the Yelp app. During the call, Stoppelman explained the opportunity facing the company and how Yelp hopes to add to additional users.

ComScore indicates that Yelp has only about 30% reach on US smartphones, so in 2015 we expanded our marketing efforts to include our first TV advertising campaign to increase awareness. Based on a survey we conducted with Nielsen in the fourth quarter, unaided brand awareness increased from 26% to 41% over the last year among US adults online. We are pleased with these results and plan to continue investing in marketing throughout 2016.

Other numbers investors might want to know
Yelp remains a speculative investment, as the company has not been consistently profitable in its history as a publicly traded firm. Instead of focusing on earnings, then, investors have seemingly put more emphasis on its future prospects. Data on Yelp's traffic, its number of reviews, and popularity of its app have helped to offer a sense of the company's potential. During the call, Krolik offered up data on these various metrics.

Cumulative reviews grew 34% year over year to approximately 95 million. Unique devices accessing our app grew 38% year over year to 20 million on a monthly average basis. Average monthly mobile web unique visitors grew 14% year over year to approximately 66 million. Average monthly desktop unique visitors were down 4% year over year to approximately 75 million. Local advertising accounts grew 32% year over year to approximately 111,000. [Plain] local businesses were approximately 2.6 million, up 31% year over year.

About that $1 billion figure...
In the past, Krolik had offered Yelp investors a long-term target for the company's revenue. Specifically, Yelp hoped to generate sales of $1 billion by 2017. That's still possible, but given Yelp's current rate of growth, seems increasingly unlikely. During the call, Krolik was asked about that target. Notably, he failed to reaffirm it.

I think we want to focus on 2016 and we've given out guidance of about 34% revenue growth, $685 million to $700 million. And that's today what we're focused on.

A long runway for local advertising
During the call, Donaker spoke about the larger opportunity for the company and how he sees its business evolving in the years ahead. Although its recent growth has been disappointing, there are still many local businesses that could be enticed to advertise on Yelp in the coming years and some additional transactional opportunities.

There's something like 20 million businesses in the US. We've just broken over 100,000 local advertising accounts. So feels like on the core business, there's still a really nice runway there. That said, we are making a lot of progress in transactions so I think in the further-out years that could become an important component of the business, but for the foreseeable future, we see local advertising as the core.

Eat24 acquisition was a success
Early last year, Yelp acquired Eat24, a food delivery start-up. In 2015, Eat24's revenue grew more than 80% on an annual basis. During the call, Stoppelman explained how the Eat24 business was able to grow so rapidly.

On Eat24, a major driver there was the integration with Yelp. We created Yelp platform a number of years ago around the time of the IPO. Eat24 was our best partner, our most successful partner. And as we have combined, we found opportunities to promote ordering particularly in search, with had a really nice impact driving you new users as well as transaction volume to Eat24. Of course a number of those users that are driven from Yelp turn into Eat24 users as well, natively on the separate app and so overall we're seeing a really nice synergy there.