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

The Dow Jones Industrial Average (DJINDICES:^DJI) is down about 37 points as of 11:15 a.m. EST as weak European data and the release of the ISM Non-Manufacturing PMI in the U.S. help to push stocks lower.

Markets in Europe sold off after the European Commission cut its forecast for employment and growth, while the European Producer Price Index, a measure of inflation, came in lower than expected. That weakness in Europe may have carried over to the U.S., where it was then exacerbated by the release of the ISM at 10 a.m. EST. That report came in better than economists had expected, suggesting that the Federal Reserve may be more likely to curtail its asset purchases.

Despite the drop in markets, a number of tech stocks were able to outperform, including Microsoft (NASDAQ:MSFT), AOL (NYSE:AOL), and Pandora (NYSE:P).

Windows Phone gets a slight boost in Europe
Data from Kantar showed Microsoft's (NASDAQ:MSFT) Windows Phone gaining traction in Europe, notably surpassing iOS in Italy. Microsoft's mobile platform also posted great growth in Germany, France, and Great Britain and increased its share of the U.S. market more than any of its rivals.

BlackBerry's rival BB10 platform, released in January, has largely been a failure. A total lack of mobile apps may have doomed BlackBerry's new handsets among consumers. A similar fate may have awaited Microsoft's Windows Phone, which, despite the growth, remains in a distant third place behind Android and iOS on a global basis.

Yet despite the challenges, Microsoft isn't giving up on Windows Phone -- far from it. Its recent purchase of Nokia's hardware business makes the company more committed to Windows Phone than ever before. Microsoft shares rose about 1.4% following the news.

AOL posts an impressive earnings beat
But AOL's gain was far more significant. The Web portal rose more than 8.5% after AOL reported earnings, beating expectations for both revenue and profit. Revenue came in at $561.3 million, beating the $549 million estimate, while adjusted earnings per share came in at $0.55, ahead of a $0.51 estimate.

Unadjusted earnings were notably lower: Profit was actually down 90% on a year-over-year basis. But that was largely due to AOL's decision to downsize Patch, a move that investors may have been awaiting.

AOL's earnings beat was fueled by growth in advertising and traffic. AOL noted that advertising revenue has now increased for the third consecutive quarter, while global advertising revenue is up for the 10th consecutive quarter. Meanwhile, traffic to AOL-owned websites was up 4% year over year, suggesting the company's properties are becoming more popular.

Pandora fends off iTunes Radio
Pandora is also becoming more popular. Its share of the U.S. radio-listening market grew to 8.1%, up from 6.6% last year. Total listener hours in October came in at 1.47 billion, up from 1.25 billion in October last year, while total active listeners increased to 70.9 million from 59.2 million last year.

October was a key month for Pandora, as it saw its biggest competition yet: iTunes Radio. Included in iOS 7, iTunes Radio gives owners of Apple devices a competing radio service. As much of Pandora's U.S. audience is using an Apple device, there was some fear that iTunes Radio could rob Pandora of listeners; yet the data released on Tuesday suggests that's not the case. Pandora (at least for now) looks resilient in the face of increased competition.

Sam Mattera has no position in any stocks mentioned. The Motley Fool recommends Apple and Pandora Media. The Motley Fool owns shares of Apple and Microsoft. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.