This has quietly been shaping up as the year when cash-rich tech darlings dig deep into their pockets to snap up other companies. Amazon.com (AMZN 1.30%) striking a deal to pay nearly $1 billion for video-sharing website Twitch late last month may be the most recent digital tech transaction, but there have actually been plenty of even bigger hookups taking place earlier this year.

Apple (AAPL 0.64%) and Facebook (META 2.98%) have struck a couple of 10-figure deals for disruptive upstarts earlier this year, and we still have another four months of potential nuptials to consider.

Accepting Facebook's friend request
Facebook initially flirted with Snapchat late last year, but Facebook didn't mope around when the fast-growing photo messaging platform reportedly rejected $3 billion offer. It got back on its mergers and acquisitions horse to negotiate the two biggest purchases in its brief corporate history.

WhatsApp came in February, turning heads for the $19 billion price that Facebook was willing to pay for the lightly monetized mobile instant messaging platform. A month later it shelled out $2 billion for virtual reality upstart Oculus VR.

Spending $21 billion on a pair of deals in a span of weeks is a pretty big deal. Facebook has made several purchases, but outside of paying $1 billion for Instagram two years ago -- weeks before going public -- it's been mostly small transactions for obscure companies.  

More shopping sprees
It wasn't just Facebook cutting its biggest deal in history. When Apple announced that it would be taking in Beats for $3 billion, it was the consumer tech giant's most valuable acquisition. Another 10-figure deal closing this deal was Microsoft's (MSFT 1.65%) $7.2 billion purchase of Nokia's (NOK -0.27%) mobile handset business. Yes, the software giant announced its bold push into smartphone hardware late last year, but regulators didn't clear the deal until April of this year. This is Microsoft's most expensive acquisition outside of its $8.5 billion deal for Skype.

Google (GOOG 1.25%) (GOOGL 1.27%) has also cut some big checks in 2014. It actually kicked things off in January with its $3.2 billion deal for learning thermometer pioneer Nest Labs. It expanded its presence in smart home gadgetry a few months later by picking up surveillance equipment maker Dropcam. 

Big deals make big sense
This brings us back to Amazon and its purchase of Twitch. It's a smart move. The video game clip-sharing site attracted 55 million unique visitors in July. This is a juicy market for Amazon on a couple of different levels. For starters it brings a fast-growing video-streaming property into its fold at a time when it's trying to make a dent in streaming. Instead of paying for content as it does with Instant Video and Prime Instant now it will have a site where content creators want to contribute to the growing vault of gameplay videos. 

Another reason why this is a move that makes a lot of sense is that Amazon will have closer ties to diehard gamers. If you're one of the 55 million people hitting up Twitch you probably have an interest in gaming, and Amazon is hoping to be a hotbed of digital distribution when it comes to games.

All of this year's other big deals make sense. Apple may seem to be overpaying for the premium headphone maker and digital music service provider but it will be able to build on Beats Music's online licenses as Beats headwear gets promoted to Apple's growing customer base.

Google is clearly making the automated home a new tech battlefront, and it's getting ahead of the pack with the purchase of two growing players that are simplifying life around the home. Microsoft's purchase of Nokia's mobile hardware unit opens up a can of worms in terms of conflict of interest, but that didn't stop Google from doing something somewhat similar with Motorola earlier. If Microsoft wants more phones running Windows it needs to make its own luck as it's doing with Nokia.

Facebook has a higher hurdle to clear in justifying its deals. Paying $19 billion for a messaging app with a very light monetization model may seem high. Shelling out $2 billion for a geek toy maker that got its start on Kickstarter may seem more like a hobby than a business pursuit. However, many investors thought that Facebook was overpaying for Instagram. It seems to have been money well spent now. 

These tech giants are cutting big deals, but it's a better place for their money to be than simply laying out on the balance sheet. Expect more big deals to come.