Apple (AAPL 0.45%) apparently has money burning a hole in its pocket because it's been on a spending spree over the past week, dropping an estimated $400 million on music recognition service Shazam, then plunking down a $390 million payment to Finisar (FNSR) for advance orders of its facial recognition technology used in the iPhone X.

While the two expenditures are for vastly different purposes -- Shazam will be a perfect complement to Apple Music and music discovery, while the Finisar deal virtually precludes rivals like Samsung (NASDAQOTH: SSNLF) from competing -- it shows Apple is serious about not only remaining competitive, but in taking the lead in product innovation.

Shazam music discovery app on Apple watch.

Image source: Shazam.

No need to go big or go home

Since its founding in 1976, Apple has made dozens of acquisitions, some big, some small, but according to a Thomson Reuters analysis of the 68 deals its made over the last three decades, only 15 of them have actually disclosed a value amount and only a half dozen have been for $100 million or more.

Shazam was Apple's fifth transaction in 2017 and there are a few more days left before the year runs out. Maybe there's still enough spare change rattling around in the tech giant's pockets to squeeze out another deal or two.

Below are the six most expensive deals in Apple history in ascending order.

6. Power Computing (Sept. 2, 1997 -- $100 million)

One of the differences that marked the trajectories staked out by Apple and rival Microsoft (MSFT 1.52%) was the latter allowed third parties to license its operating system, which is why Windows computers became so ubiquitous. Apple had always kept tight control over its proprietary system, but under CEO Gil Amelio, had started down that path. Following Amelio's ouster in 1997 and Steve Jobs return that plan was abandoned.

Jobs believed Power Computing had done more to steal sales from Apple by selling Mac clones than other players in the market. For its $100 million, Apple got Power Computing's "key assets," including marketing employees, customer databases, and most importantly, the license to distribute Mac OS products.

Flyover image of Golden Gate Bridge in Apple Maps.

Image source: Apple.

5. C3 Technologies (July 14, 2011 -- $155.4 million)

Having to rely upon a competitor is not in Apple's DNA, and needing to use Google Maps on its iPhone rubbed the company the wrong way. Enter C3 Technologies, a 3D imaging company that produces sophisticated technology to layer 3D images onto traditional two-dimensional maps.

Mapping technology had always been important to Apple, and it had previously scooped up mapping firms such as Placebase and Poly 9. Today, to get get a 3D version of a map on your iPhone, you pinch to zoom in on a city on the map, place two fingers side by side on the map, then drag up. You can also get a 3D aerial tour by choosing Flyover.

4. PA Semi (April 24, 2008 -- $268 million)

As Apple built out more portable devices, the need for low-power processors grew exponentially. While it had relied upon Intel (INTC -0.06%) for its processors, having switched from the PowerPC chip, the chipmaker had a very public profile with where it was going. Because of Apple's famed quest for secrecy, acquiring the fabless chip designer behind the PowerPC, it allowed Apple to add PA Semi's engineers to its own who were building custom chips for the iPod, iPhone, and the soon-to-come iPad.

A person putting their hand out having their fingerprints digtally enhanced.

Image source: Getty Images.

3. AuthenTec (July 27, 2012 -- $370.8 million)

As Apple was rolling out its digital wallet called Passbook along with iOS 6, the need for security was paramount, and AuthenTec was the leading developer of fingerprint recognition technology. It was licensed to various companies including Samsung, HP, Cisco, and more, and while Apple first sought to negotiate a license for itself, it ultimately decided to buy the whole company outright. Moreover, it had just introduced a new sensor specifically for near-field communications to be used in mobile commerce. Apple was on the cusp of issuing its latest iPhone (the iPhone 5) and the iPad 4, as well as the then-new iPad Mini.

2. NeXT Computer (Dec. 20, 1996 -- $404 million)

Certainly there were the technological improvements that Steve Jobs had built into his NeXT Computer that made Apple executives envious, particularly as their own efforts at upgrading the Mac OS had proved less than successful. But the most important part of the deal was to get the genius of Steve Jobs back at Apple.

While Jobs returned to Apple as only an advisor when the company bought NeXT, he subsequently became acting CEO and then CEO again, leading perhaps to the greatest revival of a company ever. Although NeXT Computer had stopped making hardware three years prior to the purchase, having become a software-only company, its NeXTSTEP formed the basis of future Mac OS's and its fingerprints remain all over OS X.

Red Beats headphones against a white background.

Image source: Apple.com.

1. Beats Electronics (May 28, 2014 -- $3 billion)

The biggest whale to be caught in Apple's net was the $3 billion acquisition of music streaming service Beats Electronics, which also made the popular Beats headphones, speakers, and audio software.

Apple already had iTunes from which it could have developed its own streaming service, but Beats brought with it a bit of celebrity. Not only Dr. Dre and Jimmy Iovine, the star-power names behind Beats, but also the celebrity endorsements that went along with the headphones. In fact, the market analysts at NPD Group said Beats commanded a 25% share of the headphone market and 46% of the dollar share last Christmas. As my colleague Rick Munarriz said, the mind-blowing $3 billion Apple spent on this company isn't extraordinary because it was a bad deal, rather because Apple hasn't found a company worth buying for even more.