IMAGE SOURCE: Glu Mobile Inc.

What happened

Shares of Glu Mobile Inc. (GLUU) declined 18.9% in 2016, according to data provided by S&P Global Market Intelligence, as the free-to-play games specialist's volatile quarterly results left the market underwhelmed.

So what

Glu Mobile investors are no stranger to volatility. Shares plunged more than 37% in 2015, as investors questioned the sustainability of its celebrity-centric game approach.

Ironically, Glu Mobile stock skyrocketed nearly 68% in February alone after the company's fourth-quarter 2015 results absolutely crushed expectations, driven by ongoing traction for its Kim Kardashian: Hollywood, Cooking Dash 2016, and Deer Hunter 2016 titles. Moreover, Glu Mobile enjoyed a strong early response to the launch of its Kendall and Kylie game later that month. 

But the good times wouldn't last long. Shares had all but given up February's big gains by the time first-quarter 2016 results were released in early May, when the company confirmed revenue had fallen 13.5% year over year, to $54 million, and translated to an adjusted net loss of $4.2 million, or $0.03 per share. To be fair, Wall Street was looking for an even wider loss on lower revenue that quarter. But Glu mobile shares plunged another 14% after management reduced its previous full-year guidance, with Glu Mobile CFO Eric Ludwig at the time blaming "softness on the tail of the Kendall and Kylie game, as well as lowering second half 2016 new title contributions."

Now what

That said, it's worth noting that the stock attempted to stage a rebound late in the year, climbing as much as 11% in a single day in late November after both its new CEO, Nicholas Earl, and its executive chairman, Niccolo de Masi, each purchased a large number of shares on the open market. This vote of confidence could be a sign of good things to come -- perhaps including a strong launch from Glu Mobile's new Nicki Minaj: The Empire game in early December -- when Glu Mobile releases its fiscal fourth-quarter and full-year results early next month.

In the meantime, however, given its relative business underperformance for most of last year, it's no surprise shares of Glu Mobile ultimately sank in 2016.