Once the gold standard of business communication on mobile devices, the BlackBerry could be approaching its expiration date.

In the last two years, BlackBerry’s market share among users in the United States has dropped from 44 percent to 12 percent, according to market research firm ComScore. With its stock in the tank, BlackBerry’s parent company Research in Motion (RIM) is talking to bankers about a possible sale among other “strategic options.” While this is all happening, more consumers and businesses are embracing Androids, iPhones and Windows phones as alternatives.

If you are still using a BlackBerry for business and are anxious to make a change, you can choose from dozens of quality devices. Here are the five best smartphones for doing business today.

Samsung Galaxy Nexus (Verizon and Sprint)

The best and brightest from Google and Samsung collaborated to create this flagship Android smartphone. Although the Galaxy Nexus is touchscreen and lacks actual keyboard buttons, the phone’s operating system has state-of-the-art virtual buttons and voice-enabled speech-to-text features that make it easy to fire off a quick email/message and even tap into longer-form documents. The phone’s 4.65-inch 1280×720 pixel curved glass display are generously sized for video conferencing, web browsing and managing documents, without making the device so large that it can’t comfortably fit into your hand or pocket. Of course, business communication is predicated on speed and processing power. Here, a dual-core 1.2GHz processor comes in handy. Network speeds vary according to the cellular carrier. Verizon and Sprint subscribers can enjoy lightning fast 4G LTE speeds, particularly when performing bandwidth-heavy tasks like downloading rich documents and participating in virtual meetings. Battery life for the Nexus is reasonably strong, and most users can last the day without charging it. While you aren’t going to win any photography awards using the phone’s front and rear-facing cameras, they are adequate for your needs.

The best things about the Nexus, however, can be found inside the phone. The Nexus line of “pure Android” phones are thankfully devoid of bloatware, so you don’t have to worry about useless pre-installed apps slowing down your device and occupying precious space on your screen. The Nexus was the first handset to run on Android’s Ice Cream Sandwich operating system, the most advanced Android software to date. Like all Android devices, the Nexus has access to more than 500,000 third-party applications. This includes hundreds of quality business and productivity apps. The Galaxy Nexus can be purchased for $199 with carrier contracts. The phones can also be acquired unlocked directly from Google for $399.

HTC Titan II (AT&T)

The biggest beneficiary of BlackBerry’s decline is arguably Microsoft and the company’s Windows Phone operating system. For large enterprises, BlackBerry and Microsoft-enabled products are almost always best for chief operating officers and other decision-makers in the corporate IT department. So if you are restricted to using a Windows phone, the HTC Titan II is far and away your best option. The Titan II comes equipped with a 4.7-inch touchscreen display, a 1.5GHz processor and a super-hero lithium battery that can survive 11-hours of continuous use. This battery life is especially helpful when you spend your day talking away on AT&T’s 4G LTE network. While Microsoft smartphones aren’t associated with apps in the same way as iPhones or Android, there are now approximately 100,000 available to download to Windows mobile devices. That way you can access compatible Office products while also enjoying tunes from Pandora and perhaps games from your Xbox LIVE account. The Titan II is available for $199 with a two-year AT&T contract.

Motorola Droid 4 (Verizon)

If a touchscreen device is not your cup of tea and you still desire the tactile experience that comes along with pressing actual buttons while you type, the Droid 4 is the smartphone you’ve been looking for. With a slide-out QWERTY keyboard with LED edge-lit keys, owning a Droid 4 is the closest thing to being able to carry around a personal computer in your pocket. The Android-powered smartphone, which runs on an earlier Gingerbread version of the operating system, also comes equipped with a 4-inch touchscreen. A 1.2GHz dual-core processor and access to Verizon’s 4G LTE network make the Droid 4 a fast and powerful option. Battery life is more than adequate. As well, when you are at the office or at home, you can use the Webtop application to plug your Droid 4 into a larger screen or monitor. The Droid 4 can be had for $199 with a two-year contract from Verizon.

iPhone 4S (AT&T/Sprint/Verizon)

The world’s most popular smartphone is also a lean, mean business machine. While many enterprise IT staffs are still reluctant to embrace Apple products, the mind-blowing success of the iPhone and its tablet cousin, the iPad, continues to break down corporate walls. While the iPhone 4S is not as physically robust as many other options (3.5-inch screen, primarily limited to 3G networks, and 8-hours of talk time), the best business, productivity and entertainment applications are still developed with the iPhone in mind first. And no other device has the voice-enabled Siri personal assistant. Worried that Apple will unveil a next-generation iPhone next week during its annual Worldwide Developers Conference? Fear not. The iPhone 4S was introduced last October, so don’t expect a new iPhone to come out until at least the fall. The 16GB iPhone 4S can be purchased for $199 with a two-year subscription to its carrier networks AT&T, Verizon and Sprint.

HTC One S (T-Mobile)

T-Mobile subscribers have more limited choices when it comes to quality, business-oriented smartphones. The newly-released HTC One S is the best option for business professionals. Although skinny at .31 inches, the HTC One S sports a 4.3-inch touchscreen and 1.5GHz dual-core processor. Battery life is solid with 10.5 hours of talk time. While T-Mobile’s 4G network does not measure up to the larger carriers, it is fast enough for virtually all of your business needs. An added bonus is that the HTC One S comes with the newer Ice Cream Sandwich operating system installed. So, unlike the Droid 4 there is no need to upgrade your software. The HTC One S can be bought for $199 with a two-year T-Mobile contract.

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