Zynga's fourth quarter revenue failed to meet analyst expectations of $201m (£131m), amounting instead to $192.5m (£125.1m) during the three months to 31 December.
The social gaming company said it lost $45.1m (£29.3m), or five cents-per-share, compared with a loss of $25.2m (£16.4m), or three cents-per-share, during the equivalent period in 2013.
Outlook for the first quarter of this year was worse than many had hoped, too – the company said it expects revenue to come in at between $155m (£101m) and $165m (£107m), which is below the average analyst estimate of $201m (£131m).
Shares fell by 10 per cent in after-hours trading following news of the poor performance and outlook.
It wasn't all bad, however – the company is expanding its user base among mobile users, with mobile bookings going up by 120 per cent in the fourth quarter.
Why it's interesting
Zynga was first brought success by the triumph of Farmville in 2009, when consumers went crazy over managing the simulated farm animals. The company continued to do well for a number of years afterwards as it released a series of relatively popular Facebook games.
But over the course of 2014, the Farmville effect wore off and shares in Zynga fell by a huge 45 per cent.
It doesn't give up easily, however – it's still in search of the next big thing. Zynga said it intends to release between six and 10 new titles this year, as well as branching out into the new territories of match-three puzzle and action-strategy gaming.
What Zynga said
Chief executive Don Mattrick remained positive about expansion in mobile:
2014 was a year of progress for Zynga -- we came together as one team and applied more discipline and rigour to our business. In the fourth quarter, we increased mobile bookings to 60 per cent of our total bookings mix, expanded our mobile audience with monthly mobile consumers up 87 per cent year over year, and grew our core franchise bookings by 35 per cent year over year.In 2015, we will focus on three priorities: driving mobile growth, launching more products in more evergreen categories and building on our social legacy.