iOS 4.3 beta is out now, and just like most developer releases, provides a pretty good preview of what we can expect in this forthcoming firmware update.

iOS 4.3 beta developers

Consistent with what we’ve previously heard, iOS 4.3 indeed comes with the Personal Hotspot feature that Apple introduced in the Verizon iPhone. But that’s not all. It also adds AirPlay support for 3rd party apps, new effects (thermal camera, x-ray, kaleidoscope, tunnel of light, collapse, turbine, enlarge) possibly for FaceTime and/or video recording, and thanks to Macrumors, a ‘Find my Friends’ feature for MobileMe. We’re not quite sure yet what and how that last feature works, but it could be Apple’s answer and alternative to Google Latitude.

The other new treats that have been discovered in iOS 4.3 are mainly for the iPad – customizable side button function, new multi-touch gestures (four or five fingers to pinch to the Home Screen; swipe up to reveal the multitasking bar, and swipe left or right between apps), and full screen iAd banners.

One caveat here though is the dropping of support for the iPhone 3G and 2G iPod Touch. As such, iOS 4.2.1, as it stands, will most likely be the last firmware upgrade for these two legacy devices. Not the best of news for owners of these two particular iOS devices, but hey, look on the bright side. You now have a good reason to upgrade to the iPhone 4.

ETA for the final build of iOS 4.3 is on February 10, and based on the timing of this beta release, we reckon its right on sked to meet that deadline.