While Apple's (AAPL -1.10%) iPhones compete with numerous smartphones running Google's (GOOGL -1.21%) Android, Samsung's (NASDAQOTH: SSNLF) Galaxies stand out as Apple's biggest competition. Samsung's phones have been generally well-received, but certain design decisions have had tech critics favoring Apple's handsets.

Samsung is widely expected to unveil its next flagship later this month. In the process, it's fixing a few major issues that have long been the bane of reviewers. Both Apple and Google investors should follow the announcement closely, as it could have immense ramifications on the entire mobile space.

Ditching plastic
Unlike Apple, which has used a combination of glass and metal on its flagship iPhones since 2010, Samsung has stuck to lightweight plastic -- and has been heavily criticized for it. The Verge's David Pierce, reviewing Samsung's Galaxy S4, wrote that the phone "has [put] Samsung back in the land of cheap, plasticky handsets." CNet said much the same, remarking that "its plastic design gives it a cheap look."

Samsung hasn't ignored its critics completely; the Galaxy Note III, released last fall, is made of faux leather -- still plastic, but much different than the cheap-feeling, bendable backs of Samsung's prior phones.

Samsung is expected to take it a step further with the Galaxy S5. Samsung is expected to offer a version of the phone made out of metal, and if it does, its critics would have less one argument to make.

Improving Touchwiz
Besides build quality, the other issue that has long plagued Samsung is Touchwiz -- the modified version of Google's Android that ships on all of Samsung's mobile devices. With Touchwiz, Samsung doesn't alter Android fundamentally (all of Google's services are still there) but it does change the look and feel of Google's operating system, mostly to its detriment.

Farhad Manjoo, writing for Slate, called Samsung's take on the dialing app "hideous" and "less functional," characterizing it as "garish shock of mismatched colors." Manjoo, a loyal Apple customer, ultimately concluded that Samsung's poor decisions had him missing his iPhone.

Of course, it isn't just the dialing app -- Samsung does this to practically everything, from the messaging app to the browser -- and it goes beyond aesthetics: Samsung's Android skin is less optimized than Google's pure version, resulting an interface that occasionally stutters and bugs out.

According to Re/code, Samsung plans to tone down from its Android tweaks, sticking to a more pure version of Google's operating system. If that's the case, Samsung's next flagship might ship with an operating system that looks and runs better than ever before.

Fewer gimmicks
In addition to toning down the tweaks to Google's operating system, Samsung also plans to include fewer gimmicky features, according to The New York Times. In the past, Samsung's handsets have included a number of additional features other Android-powered phones lack.

Some, like running two apps side-by-side, are nice. Others -- like Air View and eye-tracking -- are largely useless. And while they can mostly be ignored, their presence has hampered Samsung's phones in a number of ways.

The settings menu in the Galaxy S4 and Galaxy Note III is nothing short of a nightmare, so complex it's almost impossible to navigate. With the Note III, Samsung went so far as to include a settings search bar, suggesting that the company is well aware of the complex, maze-like nature of its settings menu. And all that extra software takes up space -- the 16GB version of the Galaxy S4 includes just 8GB of usable storage.

All of this stands in stark contrast to Apple's more functional, easier-to-use operating system. Getting rid of all that bloat would bring Samsung's handsets closer to Apple's in terms of ease of use, and in the process, improve them immensely.

No glitz and glamour
Last year, Samsung made its Galaxy S4 announcement a spectacle, hosting a major press event at New York City's Radio City Music Hall. Samsung's next flagship won't receive the same flashy introduction, but ultimately could be a far more significant handset.

Samsung's Galaxy S5 is shaping up to be a major improvement from the company's prior phone, with a better body, a more streamlined version of Google's Android, and light on gimmicks.

If that proves to be the case, Apple's iPhone will see it's greatest competition yet.