Samsung's Galaxy S3, the company's flagship smartphone for 2012, is giving Apple's iPhone some stiff competition overseas. In the UK, iPhone sales have seen a decrease following the Galaxy S3's May release date, the Financial Times reported.

The report indicates that although the iPhone 4S holds the title for most popular handset in the UK, owning 20 percent of the market, that number has fallen by five percent due to the Galaxy S3. When including sales of Samsung's Galaxy Ace and Galaxy Note, the Korea-based electronics manufacturer accounts for approximately 30 percent of the UK mobile market.

However, it wasn't until the long-awaited Galaxy S3 launched that Apple began to see its iPhone sales slow. Part of the reason Apple may have had more trouble pushing out its handsets could be that fans are holding out for its next-generation smartphone, rumored to be called the iPhone 5.

According to Bloomberg technology columnist Rich Jarolovsky, the Samsung Galaxy S3's features set the bar for Apple's upcoming handset.

It's an iPhone wannabe that also set a marker for the next iPhone, Jarolovsky told NPR when discussing the Samsung versus Apple debate. Samsung is launching it simultaneously on all the U.S. carriers, and it's substantially larger than the iPhone, but it's also thinner than the current iPhone. So it really, the form factor of it is really quite striking.

After experiencing the device hands-on, Jarolovsky pointed out some key characteristics that distinguish the device from its Apple competitor. He mentioned the S3's LTE connectivity, which is a network that enables speedy web surfing via the fastest data networks in the country.

If you're doing anything involving the Internet, it's much swifter than the current iPhone 4S, he said. Now, the expectation is that the next iPhone, which will probably be out in the fall, will be able to do LTE as well. But for right now, the Samsung S3 has it really beat in the speed category.

The two rivals aren't only dueling in the mobile device market, they've been battling in the courtroom as well. Samsung and Apple have been debating over patents since last April, and the most recent case involves Samsung's Galaxy Nexus smartphone. According to Reuters, U.S. judge Lucy Kohn granted Apple a preliminary injunction against the sale of the device on June 29. Last week, the same judge also granted a similar ruling banning sales of Samsung's Galaxy 10.1 Tab within the U.S.

Apple has made a clear showing that, in the absence of a preliminary injunction, it is likely to lose substantial market share in the smartphone market and to lose substantial downstream sales of future smartphone purchases and tag-along products.

Samsung's Galaxy S3 has been in high demand in the U.S., resulting in release date set backs across carriers. For AT&T, the smartphone is set to launch on July 6, and the device is confirmed to receive the latest Android operating system upgrade to Jelly Bean in the fourth quarter. Apple may be winning in the courts, but if the trends in the UK keep up, Apple will have to come back strong with its next generation smartphone.