Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of freemium game specialist King Digital Entertainment PLC (KING.DL) were up 12.9% as of 1:40 p.m. Friday after the company announced stronger-than-expected fourth-quarter results.

So what: Quarterly adjusted revenue fell 7% year over year to $559.2 million, which translated to a 10.9% decline in adjusted earnings per share to $0.57. And gross bookings -- a key metric for measuring in-game virtual goods purchases -- fell 7.2% to $586.3 million. That might not sound encouraging, but analysts were only expecting earnings of $0.47 per share on sales of $519.9 million. 

King Digital also noted its board declared a special dividend to shareholders of $0.94 per share -- or $300 million in aggregate -- to be paid on March 24, 2015, to shareholders of record as of March 4. King also stated it has already repurchased nearly 750,000 shares for roughly $10 million under a $150 million share repurchase program approved on Jan. 29, 2015.

Finally, King Digital announced on Feb. 6, 2015, it had signed an agreement to acquire Z2Live, a Seattle-based game development company, for $45 million in cash and up to $105 million of additional cash linked to future revenue generated by certain games launched by Z2 over a specific period.

Now what: That should help King Digital further reduce its reliance on its popular Candy Crush Saga titles, which by themselves generated a whopping 45% of the company's total gross bookings in the fourth quarter. To its credit, however, that's a huge decrease from the 78% of total bookings Candy Crush generated in the year-ago period.

In the end, however, one earnings beat still doesn't make a successful long-term business. And while King Digital could certainly continue to stem the decline of its bookings, revenue, and earnings, I'm still too skeptical of the sustainability of the free-to-play game making industry to hop on board with the bullish crowd.