1. What is Android?
Answer : One of the most widely used mobile OS these days is ANDROID. Android is a software bunch comprising not only operating system but also middleware and key applications. Android Inc was founded in Palo Alto of California, U.S. by Andy Rubin, Rich miner, Nick sears and Chris White in 2003. Later Android Inc. was acquired by Google in 2005. After original release there have been number of updates in the original version of Android.
2. Explain the Architecture of android ?
Answer : The main components of the Android architecture:
1. Applications: These are applications written in Java such as calendar, email client, SMS program..
2. Application Framework: This is the skeleton or framework which all android developers has to follow.
The architecture is well designed to simplify the reuse of components. Think of the application framework as a set of basic tools with which a developer can build much more complex tools.
3. Libraries: This layer consists of Android libraries written in C, C++, and used by various system. These libraries tells the device how to handle different kinds of data and are exposed to Android developers via Android Application framework. Some of these libraries includes media , graphics,etc..
4. Runtime Android: This layer includes set of base libraries that are required for java libraries.
5. Kernel – Linux: This layer includes Android’s memory management programs, security settings, power management software and several drivers for hardware , file system access, networking and inter-process-communication. The kernel also acts as an abstraction layer between rest of the software stack and hardware.
3. What is the future scope of Mobile Application developers?
Answer : There’s a huge demand for mobile applications now, with the mobile devices evolving to a state that you can actually do stuff (mostly bigger display and higher processing power). It is not a market that is mature now, so there are a lot of opportunities – explaining the big number of players joining the game.
As the market matures, big players are going to stand out, making the competition tougher, so I think it’s save to say the single players will have a harder time competing.
4. What is Android Runtime?
Answer : Every Android application runs in its own process, with its own instance of the Dalvik virtual machine. Dalvik has been written so that a device can run multiple VMs efficiently. The Dalvik VM executes files in the Dalvik Executable (.dex) format which is optimized for minimal memory footprint. The VM is register-based, and runs classes compiled by a Java language compiler that have been transformed into the .dex format by the included “dx” tool.
The Dalvik VM relies on the Linux kernel for underlying functionality such as threading and low-level memory management.
5. What are the features of Android?
Answer : Android OS 2.0 features :
The most interesting feature of Android OS 2.0 is the free Google maps navigation in selected areas .
Android 2.0 supports Bluetooth version 2.1.
New Android global search function that can search the phone for everything from SMS, MMS, email messages, web, contacts etc. to calender entries.
Native webkit browser will support support HTML 5 and other new web standards.
Multiple screen resolutions possible.
Excellent text-to speech API on which we can expect good applications.
6. Why to use Android?
7. Describe a real time scenario where android can be used?
Answer : Imagine a situation that you are in a country where no one understands the language you speak and you can not read or write. However, you have mobile phone with you.
With a mobile phone with android, the Google translator translates the data of one language into another language by using XMPP to transmit data. You can type the message in English and select the language which is understood by the citizens of the country in order to reach the message to the citizens.
8. What are the advantages of Android?
Answer : The customer will be benefited from wide range of mobile applications to choose, since the monopoly of wireless carriers like AT&T and Orange will be broken by Google Android.
‘Features like weather details, live RSS feeds, opening screen, icon on the opening screen can be customized
Innovative products like the location -aware services, location of a nearbyconvenience Store etc., are some of the additive facilities in Android.
How to select more than one option from list in android xml file? Give an example. Specify android id, layout height and width as depicted in the following example.
9. What Virtual Machine Android runs on?
Answer : Dalvik virtual machine