Diversity. iOS 4.0 -- or more specifically the iPhone it runs on -- is available only from one wireless carrier in the United States: AT&T. It is also only available on one form factor. There are slight variations between the iPhone 3G, iPhone 3G S, and upcoming iPhone 4 -- but for all intents and purposes it is the same hardware platform.
For businesses that are already contracted with another carrier -- like Verizon Wireless, Sprint, or T-Mobile -- iOS 4.0 is not an option. Organizations that want a physical keyboard or a different form factor will appreciate the diversity of smartphone hardware available running Android.
Winner: Android 2.2
Management tools. The iPhone has generally been perceived as a consumer gadget first and foremost. However, Apple revolutionized the game, and more or less erased the line between consumer and business when it comes to smartphones. Over time, Apple has developed a fair set of tools for IT administrators to be able to provision, deploy, monitor, and manage iPhones in the enterprise. Apple has also made strides in strengthening the security of the iPhone.
There are third-party management frameworks such as Good for Enterprise that enable IT administrators to manage Android devices, but by itself Android is still playing catch up in the enterprise tools department.
Winner: iOS 4.0
So that leaves us with three wins for iOS 4.0, three wins for Android 2.2, and one tie. The bottom line, though, is that "best" or even "better" is a subjective measurement tainted by opinion and personal preference. As noted, in some cases where the company is already under contract with a given wireless provider, the decision may be more or less dictated by what's available from that carrier.
In selecting a smartphone platform for the enterprise, IT administrators and business professionals need to keep these factors in mind, but these are by no means the only factors. Signal strength for a given carrier in your region, whether or not the smartphone will work globally for users that travel frequently, how the smartphones fit with any data protection or information security compliance requirements, and a myriad of other factors must also be taken into consideration to determine what is "better" or "best" for your specific situation.
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