What it fixes
A page dedicated to the release on Apple's website details a dozen major enhancements including:
- Decrease in call set-up failures and dropped calls.
- Significantly better battery life for most users.
- Dramatically reduced time to backup to iTunes.
- Improved email reliability, notably fetching email from POP and Exchange accounts.
- Faster installation of 3rd party applications.
- Fixed bugs causing hangs and crashes for users with lots of third party applications.
- Improved performance in text messaging.
- Faster loading and searching of contacts.
- Improved accuracy of the 3G signal strength display.
- Repeat alert up to two additional times for incoming text messages.
- Option to wipe data after ten failed passcode attempts.
- Genius playlist creation [Illustrated by one reader] .
How to install
Before installing the update, make sure you are using iTunes 8 [Download Link], then connect your iPhone to your computer.
- When iTunes opens, select your iPhone under Devices in the Source List on the left.
- In the iPhone Summary pane, click Check for Update.
- Click Download and Install. Do not disconnect your iPhone until the update has finished.
iPhone Software 2.1 also patch six security vulnerabilities.
- An application may be able to read another application's files.
- Multiple vulnerabilities in FreeType v2.3.5.
- mDNSResponder is susceptible to DNS cache poisoning and may return forged information.
- Predictable TCP initial sequence numbers generation may lead to TCP spoofing or session hijacking.
- An unauthorized user may bypass the Passcode Lock and launch iPhone applications.
- Visiting a maliciously crafted website may lead to an unexpected application termination or arbitrary code execution.
Some of the other enhancements and observations reported by readers thus far:
- No sign of background push notification or turn-by-turn GPS support.
- The texting memory leak problem seems to be fixed.
- Apps are running a lot faster.
- No scrolling lag, faster launching of SMS app.
- New "3G" logo in the menu bar sans box.
- Updating applications keeps their icons in place on the home screen.
- App syncs still sluggish compared to media syncs.
Readers are encouraged to share their own discoveries in the AppleInsider forum thread for this article.