Samsung (OTC:SSNLF) has certainly seen better days.

Late last month, the South Korean tech giant reported its quarterly results. On an annual basis, Samsung's profits fell 27%, and sales of its mobile phones dropped 21%. This isn't just an unfortunate aberration -- Samsung's mobile business has been in decline for nearly a year.

Chinese competitors, most notably Xiaomi, have been an increasingly large thorn in Samsung's side, costing it perhaps millions of handset sales at the low-end. But there's no doubt Apple's (NASDAQ:AAPL) iPhone 6 and iPhone 6 Plus are having an effect as well: sales of Samsung's flagship Galaxy S5 and Galaxy Note 4 have also been disappointing.

But while Samsung is certainly down, it may not be out -- its next handset, the Galaxy S6, could be the greatest smartphone ever made.

1. Amazing specs
Samsung's phones have never lacked for power: Its flagship Galaxies have always boasted cutting edge processors, tons of ram, enormous batteries, and high-resolution, quality displays. Samsung also included hardware features like NFC and LTE radios long before Apple.

But in almost all these categories, Apple has caught up -- and in some instances, it has surpassed Samsung. The iPhone's processor, in particular, has been ahead of Samsung's offerings for over a year, as Apple was the first major handset vendor to offer a phone with a 64-bit processor.

The Galaxy S6 could see Samsung retake the lead.

Samsung is widely expected to use a 64-bit, eight-core processor for its Galaxy S6. That might've been Qualcomm's Snapdragon 810, but Samsung is thought to have ditched Qualcomm's latest offering in favor of its own Exynos 7420. With its 14-nanometer construction, the Galaxy S6's processor could prove faster than Apple's competing A8.

2. A premium, unique design
But more important than the processor may be the phone's design. Samsung's Galaxy phones have long been criticized for their flimsy plastic backings, and though there's really no evidence to suggest that this affects sales -- about three-quarters of smartphone owners use a case -- it may, at the very least, swing tech reviews in Samsung's favor.

Samsung has spent the last few months reshuffling its design team. It replaced its mobile design head in May, and hired a designer from Tangerine (Jony Ive's previous employer) last month.

In August, it released the Galaxy Alpha. Compared to the Galaxy S5, the Alpha had slightly lesser specs, but sported a higher-quality metal frame and slimmer profile. The Alpha appeared to be a sort of prototype device, hinting at a future design aesthetic that could be applied to all of Samsung's phones. More recently, leaked images of the Galaxy S6's frame (via Android Authority) appear to show a phone that will -- like the Galaxy Alpha -- sport a metal chassis.

But the Galaxy S6's display could be even more significant than its frame. Ahead of the Galaxy S6's unveiling, Samsung has released a teaser image suggesting that the Galaxy S6 will boast a curved display. Of course, it wouldn't be Samsung's first phone with a curved display -- it released the Galaxy Note Edge last fall -- but it would be its first flagship.

Samsung's larger displays gave it an advantage over Apple's iPhones in previous years, but the release of the iPhone 6 and iPhone 6 Plus has leveled the playing field. Offering the only flagship phone with a curved screen could give Samsung a new selling point to exploit. Like a multi-monitor setup enhances desktop productivity, a phone with curved sides could offer a better mobile experience. Apps could sport dedicated taskbars; mobile games could make use of the extra screen real estate.

3. Better software
has made a host of improvements to Android in recent years, significantly boosting the stability, speed, and features of its mobile operating system. Unfortunately, many of those improvements have not translated to a better experience for users of Samsung's Galaxy phones.

To date, Samsung has used a modified version of Android -- dubbed TouchWiz -- that sports Google's apps and services, but suffers from a lousy, somewhat sluggish interface, duplicative apps, and garish color palette. Google's own phones -- the Nexus 4, 5, and 6 -- have been praised by tech reviewers for their use of stock Android, a version of Android free from the many nasty modifications Samsung (and other Android OEMs) often make to the operating system. Nexus phones, however, have not sold in massive quantities, as they haven't enjoyed much marketing or carrier support.

Samsung's Galaxy S6 wouldn't face those issues. According to SamMobile, Samsung is taking a Nexus-like approach to the Galaxy S6, and plans to ship the phone with a version of Android much closer to Google's. Unnecessary apps and features will be made available for download, but won't be forced on to users, and the phone should run faster and more stable.

Samsung is down, but not out
The Galaxy S6 could be the most important phone Samsung has ever released. With its TV, appliance, and semiconductor businesses, Samsung isn't as dependent on its mobile phones as Apple. But in recent years, most of the growth in Samsung's earnings has come from its mobile division.

The Galaxy S6 is likely to be an expensive handset, and it won't solve Samsung's problems with the increasing number of low-end competitors. But it could give it a super phone fully capable of taking on Apple's best handsets. Investors in the mobile space should keep a close eye on its March 1 event.