Google Inc.'s newest version of its open-source Android mobile operating system is set to launch next month, but it's only going to be available on the Galaxy Nexus device, possibly until the end of the year. Plenty of the other Android devices out there will get the 4.0 (Ice Cream Sandwich) update, but it's just too early to know which ones and when. Samsung is the manufacturer who's making the Nexus, so its high-end devices will probably be the first to get it, followed by the Motorola Droid series.

Anyone planning to pick up the Nexus will want to know exactly what comes with this unique smartphone, so here is a quick guide to Android 4.0's top five new features. The operating system got a complete makeover and combines the best features of its predecessors, Gingerbread and Honeycomb. In fact, one of Android 4.0's big selling points is that it can be used in both mobile phones and tablets.

As Siri voice recognition was to the iPhone 4S, so the Face Unlock app is to Android 4.0. It might sound like a gimmick, but if it works as advertised, it will make Android 4.0 devices hard to resist. This fun feature uses the front facing camera on your device to compare your face it to an image of you already stored in the device's memory. It uses facial recognition to unlock the smartphone to its rightful owner. It's supposed to be foolproof so a stolen device couldn't be fooled by holding up a picture of the phone's owner to unlock it. Additionally, if you're just not in the mood for smiling at your phone, you can use a PIN to unlock it too.

Photo sharing is one of the best parts of the mobile revolution. Just look at how many photo apps there are and it's obvious people love to share all kind of images.Android 4.0's new camera capabilities add continuous focus, zero shutter lag exposure and decreased shot-to-shot speed when taking photos. A Stabilized image zoom lets users compose photos and video in the way they want, including while video is recording. There is a built-in face detection that locates faces in the frame and automatically sets focus. Furthermore, there's a single-motion panorama mode where the camera pieces together a set of continuous images into a single panoramic photo.

Photos are great and all, but everybody knows the whole reason we have data plans on our devices now is to surf the Web. Google knows this and has improved the Android 4.0 stock browser to accommodate your Web savvyness. It's faster, features a refined tab manager and the ability to sync your bookmarks with Google Chrome. Ice Cream Sandwich also features a new design that lets you quickly swipe through your inbox and search messages even when you're offline. Part of that Web browsing experience involves organizing personal, work, school, and social agendas. Calendars are now color-coded and users can swipe left or right to change dates and pinch to zoom in or out of agendas. There is also new visual voicemail features that integrate incoming messages, voice transcriptions, and audio files from one or more providers.

Finally, Android 4.0 the home screen folders and favorites tray let users group their apps and shortcuts just by dragging one onto another. On smaller-screen devices, the home screen will include a customizable favorites tray that can be seen from all home screens. Users can drag apps, shortcuts, folders, and other priority items in or out of the favorites tray for instant access from any home screen.

Let us know in the comments which version of Android you have and what it really needs to improve.

MUST READ: Samsung Future is Now: Flexible Screen Device to Launch in 2012 [VIDEO]

MUST READ: Galaxy Nexus vs HTC Titan: Battle for Smartphone Supremacy (VIDEO)