Android

The Applications layer hosts all Android and third-party applications, and several or more third-party applications can execute simultaneously. However, as noted, doing so can shorten battery life.

Beneath the Applications layer is the Android Frameworks layer. This layer consists of Java classes that provide application functions such as window management, window content display, application messaging, and handling phone calls. Obviously the interface Android presents at this level uses the Java programming language, and because the source code is available, you can modify these classes to extend their capabilities or over override their behavior. Note that some of the lower levels in the stack present C++ interfaces.

Next on the software stack comes the Libraries and Runtime layer. The libraries implement 2D and 3D graphics support, along with multimedia content decoding. This layer has engines to support application features, such as a SQLite database engine and WebKit, which handles web content rendering.

Like Java ME, Android strives for hardware independence by using a bytecode interpreter to execute Android applications. However, it doesn't use Sun's JVM, but instead uses its own Dalvik Virtual Machine (DVM). The advantage to Android's use of a different bytecode interpreter is that the DVM was designed so that multiple instances of it can run, each in their own protected memory space, and each executing an application. While this approach offers stability and a robust environment for running multiple applications, it does so at the expense of compatibility with Java ME applications.

The lowest layer of the stack is the Linux kernel. It provides preemptive multitasking and system services such as threads, networking services, and process management. It handles all low-level drivers and manages the device's power




My favorites device right now is the

Samsung Behold II which is now official. It is offered by T-Mobile and run on Android OS. Behold II is also known as SGH-t939 and is quite an impressive phone.

The device has a 3.2″ AMOLED touch-screen, supports 3G networks and T-Mobile promises it will be out before the holidays.

Samsung Behold II will be Samsung’s first Android-powered device with T-Mobile and will have an integrated GPS receiver
so you can take full advantage of Google Maps, and hundreds of others apps that uses location information.

Samsungs Touchwiz 2.0 and Cube Interface is pretty slick and is a great demonstration of what Open GL can deliver on handled handset



Samsung Behold II Feature list