In April 2012, Apple started shipping a slight variant on the iPad 2 that remains for sale even as the third-generation iPad has become the mainstay of the line. This new version of the iPad 2 — labeled internally as “iPad 2,4” — uses a 32 nanometer version of Apple’s A5 chip that replaces the 45nm version in the previous iPad 2 model. The processing performance is the same, but AnandTech is reporting that the 32nm model has notably better battery life (and a lower manufacturing cost). Alas, there is no way to know if any given iPad 2 uses the new chip without running an app that reports on the internals. follow link
How to Know Your iPod Model
If you have an old iPod but aren't sure exactly which model it is, check the info at the Web page linked below. You'll find lots of photos and information that will help you determine exactly which model you have.
Visit Identifying iPod Models
Quietly Revised iPad 2 Sports Better Battery Life