iPad-2When Apple revealed their new iPad, they also dropped the price of the iPad 2 by $100. We figured that was pretty much it for the iPad 2. It would not be in the news again until either the price changed again, or it was discontinued.

But Apple does have a knack for doing the unexpected (sometimes). According to a new report from Anand Lai Shimpi on AnandTech.com, Apple is making some hardware improvements to the iPad 2 by slipping in a new, unannounced, version.

Shimpi, who is the CEO of AnandTech, identifies it as an iPad 2.4. He writes that this new iPad 2 replaces the previous iPad 2 WiFi (or 2.1) version. He said both versions have an identical appearance, and that it’s impossible to tell them apart unless the unit is opened up.

So, what’s different? In the iPad 2.4, the chip is cast with a smaller die, and uses less power. According to Shimpi, that will provide an estimated 2 hours more of battery life than the older iPad 2.1. “We measured a 15% increase in our web browsing battery life, a nearly 30% increase in gaming battery life and an 18% increase in video playback battery life. Although Apple hasn’t revised its battery life specs, the iPad 2,4 definitely lasts longer on a single charge than the original iPad 2,” said Shimpi. Because it uses less power, the tablet also runs cooler.

Shoppers seeking to pick up one of these new iPad 2.4 models may be in for a challenge though. Shimpi said they are packaged the same. “The newer iPad 2,4 units should come with iOS 5.1 preloaded, while any older iPad 2,1 stock may have 5.0.1 or older.” he wrote in his analysis. Note the word ‘should.’ He also said the only way to tell for sure is by running an app that provides information about the hardware, such as Geekbench, Linpack, or Battery Life Pro.

Of course, apps can only be installed and used after the purchase it made.