Investors were eager to snatch up shares of AppLovin (NASDAQ: APP) after the company reported its fourth-quarter results. The company, which helps app developers monetize their apps with advertising, reported mixed results for the quarter, but investors reacted to the AppLovin's better-than-expected revenue guidance of the first quarter. AppLovin's fourth-quarter sales fell 11.5% to $702.3 million, but that was good enough to beat the consensus estimate of $689.9 million.