As Apple CEO Steve Jobs promised earlier this week in his iPod and iTunes-focused music announcements, the iPhone 2.1 software update is now ready for installation by all iPhone owners. The update became available this morning, and Apple even went so far as to post a notice on its home page to alert iPhone owners of the free update. The 2.1 software update is a relatively big chunk of data — 237.8 MB worth. “It fixes lots of bugs. You’ll get fewer call drops. You will get a significantly improved battery life for most customers,” Jobs told reporters.