Android phones have a bad history of not getting the latest OS upgrades, often leaving them several versions behind, says a new study.

Tracking 18 different Android phones shipped in the U.S. through the middle of 2010, the Understatement’s Michae

l Degusta found that most have not received major OS upgrades or even minor support patches, even though they’re still under contract.

Pointing to one example, Degusta said that the Samsung Behold II on T-Mobile was supposed to be upgraded to Eclair, aka Android 2.1. But by the time the phone hit the market, it was already two versions behind, and then Samsung never bothered to upgrade it.

As another example, the Motorola Devour on Verizon was already one version behind on the OS when it debuted in early 2010. Less than a year later, it was three major versions behind.

Breaking down his study, Degusta uncovered several specific items:

7 of the 18 Android phones tracked never ran a current version of the operating system.
12 of 18 only ran a current version of the OS for a matter of weeks or less.
10 of 18 were at least two major versions behind within their two-year contract.
11 of 18 stopped getting any support updates less than a year after release.
13 of 18 stopped getting support updates before sales were halted or shortly thereafter.
15 of the 18 don’t run Gingerbread, which shipped in December 2010.
With the debut of Ice Cream Sandwich, every device tracked will be another major version behind.
At least 16 of 18 will almost certainly never get Ice Cream Sandwich.

Beyond not receving a recent version of the Android OS, many phones are also missing out on support updates, especially those that have been discontinued. That leaves such phones vulnerable if a security or privacy issue hits an older version of Android, contends Degusta.

In comparison, Apple has a strong history of supporting the last several models of its iPhones through iOS upgrades and updates, the study noted.

But therein lies the rub.

As both phone maker and OS supplier, Apple controls the entire process and can roll out major iOS releases or smaller security updates that most iPhone owners can quickly install.

Android is more a case of too many cooks in the kitchen. As Degusta notes, “a big part of the problem is that Android has to go from Google to the phone manufacturers to the carriers to the devices, whereas iOS just goes from Apple directly to devices.”

To try to remedy the problem, Google announced an effort this past May to create guidelines on how quickly Android devices would get updated. Dubbed the Android Update Alliance by some, this effort was presumably supposed to lead Google to work with the device makers and carriers to keep Android phones better updated.

But like Degusta, tech blogger site Android and Me found in August that only a small number of Android phones were running the latest version of the operating system, showing that Google still has its work cut out for it.

Google did not immediately respond to CNET’s request for comment.