A slow day from the markets didn't stop today's top movers, but the S&P 500 (^GSPC -0.88%) crept its way to a gain of just 0.05%, or less than one point, to hold steady below the 2,000-point mark. Earnings season marched on with another slate of major reports today; but the biggest news early on in the market's day came out of China.

Beijing sparked a new round of optimism among economists concerned over China's recent slowing GDP growth today as the country's flash Purchasing Manager's Index, a measure of manufacturing activity, jumped to an 18-month high. At a reading of 52%, China's flash PMI showed healthy expansion in manufacturing at a full two points above the breakeven level of 50% that marks neither expansion nor contraction. More positively, today's recording indicated that expansion jumped by more than a full percentage point above June's final record of 50.7%.

China's Gate of Heaven in the Forbidden City. Source: Wikimedia Commons.

China's in no way out of the woods yet for international investors eager to capitalize on recent weakness in Asia's largest economy. Beijing's barely clinging to 7.5% annual GDP growth, the country's long-term target for economic stability, while the hard-hit housing market and receding foreign investment have pressured the Chinese market. However, easing measures and looser credit have spurred hope that the economy will continue its growth through the end of 2014, particularly as the U.S. and European markets gain momentum. This is a trend that would go a long way to boosting the Chinese export sector, a major growth driver of the country's economy. It's a wait-and-see game in China, however, as Beijing, so far, has refrained from more substantive easing measures.

The market today keyed in on earnings more than China, however -- and it was strong earnings reports that buoyed two of today's top stocks, with both Nokia (NOK 2.03%) and Under Armour (UAA 1.81%) soaring up the charts.

Source: Wikimedia Commons

Under Armour came through in the clutch with its earnings today, notching astronomical 34% year-over-year revenue growth in its most recent quarter en route to a 14.7% stock gain. While the athletics retailer's earnings were flat through the second quarter, Under Armour hiked both its operating income and revenue outlooks for the full year -- the latter in a big way, with the company boosting its revenue guidance from a 25% full-year gain to a 29% increase.

This athletics giant has made a habit of reeling in superb growth as of late, but it's perhaps internationally where Under Armour's connecting with its biggest hits. International sales only represent 8% of the company's overall revenue, but jumped by a sterling 80% year over year in the most recent quarter. North America still dominates Under Armour's financials, but if this juggernaut can continue making inroads overseas, it will be in prime position to challenge chief rival Nike on a global scale -- something that bodes well for a stock that's already shot up by 96% during the past year.

Nokia also called in a great performance this earnings season as the stock jumped by 8.2%. Even after the company sold off its wireless business to Microsoft in a $7.5 billion deal earlier this year, Nokia still managed to post earnings of $0.06 per share, a mark that topped analyst projections. Services took a beating in the quarter, with a 19% revenue drop, but sales of equipment spiked by 6%.

While developed markets are hurting Nokia's financials, China has become a huge growth driver for this company. Overall revenue from Asia's largest market climbed 18%. That's managed to keep the company's operating margins above estimates as it charts a post-wireless life. If China can continue providing strong growth while Nokia searches to turn around in developed markets, this stock may be a surprise in waiting, even without its wireless unit.

Perhaps the best stock of the day wasn't boosted by earnings, however. Real estate website operator Trulia (NYSE: TRLA) erupted for a 32.4% gain today after reports emerged of rival Zillow's (ZG -0.17%) interest in a possible takeover. Zillow's stock posted its own impressive run on the news in jumping by more than 15% today. While any deal is only in a reported stage as of now, a possible merger could result in a combined company dominating the online real estate listing space. Bloomberg reported 85 million visitors to the two sites combined last month, per data from ComScore.

Trulia is already rising in a big way, with revenue at the company projected to climb by 76% through the full year. If Zillow's interest becomes more than just reports, however, shareholders could be in for an even more welcome surprise.