The Dow Jones Industrial Average (DJINDICES:^DJI) finished down 96 points for the week, or 0.56%. Among the more interesting tech stocks during the week were freshly listed GoPro (NASDAQ:GPRO), its chip-partner Ambarella (NASDAQ:AMBA), and software giant Microsoft (NASDAQ:MSFT).

The GoPro HERO3. Source: GoPro.

GoPro popped and then popped some more
GoPro, which makes highly popular wearable digital cameras, finished the week up a cool 49% from its $24 IPO price. This is a hot technology company, with buyers apparently just as interested in its stock as consumers are in its cameras.

The stock surged 30.5% on its first day of trading. As if that weren't enough, investors pushed the stock up to a high of $40.47 per share on its second day of trading -- yet another 29%-before the stock settled to close at $35.76, or 14.10%.

During 2013, GoPro generated $986 million in sales and $60.6 million in net profit, valuing the company at roughly 4.46 times sales and 72 times net income. This is extremely steep, but if the company can continue to post gangbusters growth over the next several years, its valuation may be justified. It pays to be careful, though, as based on where the stock is trading, a lot of optimism seems to be baked in.

Derivative play Ambarella pushes higher, too
Ambarella, which underwhelmed at its own IPO just a few years ago, has been doing extremely well following multiple quarters of strong revenue and profit growth. That its chips are designed into GoPro wearable cameras is no small part of the company's success.

The company's shares moved up 4.6% for the week and are now up approximately 42% since its $21.91 low hit in early May. This move was no doubt fueled by optimism surrounding the GoPro IPO. The general line of thinking seems to be that with a nice cash infusion, GoPro will be able to expand significantly, bringing Ambarella along for the ride. 

Though Ambarella is also looks pretty pricey, trading at 26.58 times this year's consensus earnings, the sell-side is looking for some pretty serious growth in the following year, with revenue growth expected to accelerate to 21.50% and earnings-per-share growth to come in above that at 25.6%. If Ambarella can post these kinds of growth numbers and successfully fend off any potential new competitors to this space, it could continue to move higher over the long term.

Microsoft hits a new 52-week high
Microsoft, the software giant that many had written off as dead money, has been on a very nice run lately. The shares hit a new 52-week high of $42.29 during Friday's session before closing at $42.25. Keep in mind that though the Dow was down 0.56%, Microsoft closed the week up a cool 1.36%.

Microsoft's Nokia X2 handset -- in green! Source: Microsoft/Nokia.

During the week, Microsoft launched yet another Android phone called the Nokia X2. This is a low-end device aimed at the $135 price point, sporting 1GB of memory, 4GB of storage, and a 4.3-inch display, and it features a low-end 1.2 GHz Snapdragon 200 processor. Note that it doesn't run Google's version of Android, similar to Amazon's Kindle Fire and Fire Phone, and instead requires use of Microsoft services.

While Microsoft certainly has the financial wherewithal to keep pushing into the smartphone market -- and in particular the low end of the market -- it'll be tough to compete with the app ecosystem that Android offers, as well as the already formidable installed base. Emerging markets seem to be the company's best shot, though Google's Android One initiative, which helps OEMs build $100 Android smartphones, could prove a significant headwind to meaningful Windows Phone adoption.