Apple announced during its press conference on Wednesday that the latest version of its mobile operating system would become available for download later in the day. iOS 5.1 has now been released for the iPad 2, iPad, iPhone 4S, iPhone 4, iPhone 3GS and second and third-generation iPod touch handhelds, and the new iOS build brings Japanese language support for Siri along with a number of additional updates. And ridiculous though it may be, AT&T iPhone owners will now see “4G” in place of 3G next to their signal bars while connected to HSPA. We detailed key changes in our exclusive hands-on with the software last month. iOS 5.1 is currently in the process of being made available through iTunes and over the air, but impatient users can download the appropriate update via the read link below.