(1) What is Android ? 
 Ans:- Android is an open-source, Linux-based operating system that is used in mobiles, tablets, televisions etc. 

(2) Who is the founder of Android ?

Andy Rubin. 

3) What are the code names of android? 

1. Aestro 2. Blender 3. Cupcake 4. Donut 5. Éclair 6. Fro yo 7. Gingerbread 8. Honeycomb 9. Ice Cream Sandwich 10. Jelly Bean 11. Kitkat 

(4) What are the advantages of android? 

Ans:-Open-source: It means no licence, distribution and development fee. Platform-independent: It supports windows, mac and Linux platforms. Supports various technologies: It supports camera, bluetooth, wifi, speech, EDGE etc. technologies. Highly optimized Virtual Machine: Android uses highly optimized virtual machine for mobile devices, called DVM (Dalvik Virtual Machine).

(5) Does android support other language than java?

Ans:-Yes, android app can be developed in C/C++ also using android ND K (Native Development Kit). It makes the performance faster. It should be used with android SDK. 

(6) What are the core building blocks of android? 

Ans:-The core building blocks of android are: • Activity • View • Intent • Service • Content Provider • Fragment etc

.(7)What is Activity ?

Ans:-Activity is a single screen in supporting java code that is called a activity

  (9) What is view in android ? 

Ans:- A view is it the UI element such as button label tablet etc Anything that you see is a view. 

(10)What is Intent ?

Ans:- Notification message to the user from android embed device can be display using intent that is called a intent. ?

(11)What is  Service

 Ans:-A service is a background process process that can run for a long time that is call a service .There are two types of services local and remote. Local service is accessed from within the application whereas remote service is accessed remotely from other applications running on the same device.

(10)What is Fragment ?

Ans: Ans-Fragment is a part of Activity by the help of fragment, we can display multiple screen on one activity that is call a fragment .

(12) What is Content Provider?

Ans:-Content Provider or used to share data between the applications, that is called a content Provider.

(13) What are the key components of Android Architecture?

Ans:-Android Architecture consists of 4 key components:
- Linux Kernel
- Libraries
- Android Framework
- Android Applications

(14)What are the advantages of having an emulator within the Android environment?

Ans:-The emulator allows the developers to work around an interface which acts as if it were an actual mobile device.
- They can write, test and debug the code.
- They are safe for testing the code in early design phase

(15) Tell us something about activity Creator ?

Ans:-- An activity Creator is the initial step for creation of a new Android project.
- It consists of a shell script that is used to create new file system structure required for writing codes in Android IDE.

(16)What do you know about Intents?

Ans:- Notification messages to the user from an Android enabled device can be displayed using Intents. The users can respond to intents.
- There are two types of Intents - Explicit Intent, Implicit Intent.

(17) What is an Explicit Intent?

- Explicit intent specifies the particular activity that should respond to the intent.
- They are used for application internal messages.

(18) What is an Implicit Intent?

- In case of Implicit Intent, an intent is just declared.
- It is for the platform to find an activity that can respond to it.
- Since the target component is not declared, it is used for activating components of other applications.

(19) What do intent filters do?

- There can be more than one intents, depending on the services and activities that are going to use them.
- Each component needs to tell which intents they want to respond to.
- Intent filters filter out the intents that these components are willing to respond to.

(20)Where are lay out details placed? Why?

- Layout details are placed in XML files
- XML-based layouts provide a consistent and standard means of setting GUI definition format.

(21)What do containers hold?

- Containers hold objects and widgets in a specified arrangement.
- They can also hold labels, fields, buttons, or child containers. .

(22) What is Orientation?

- Orientation decides if the LinearLayout should be presented in row wise or column wise fashion.
- The values are set using setOrientation()
- The values can be HORIZONTAL or VERTICAL

(23) What is it important to set permissions in app development?

- Certain restrictions to protect data and code can be set using permissions.
- In absence of these permissions, codes could get compromised causing defects in functionality.

(24) What is AIDL?

- AIDL is the abbreviation for Android Interface Definition Language.
- It handles the interface requirements between a client and a service to communicate at the same level through interprocess communication.
- The process involves breaking down objects into primitives that are Android understandable.

(25) What data types are supported by AIDL?

AIDL supports following data types:
-string
-List
-Map
-charSequence
and
-all native Java data types like int,long, char and Boolean

(26) Tell us something about nine-patch image.

- The Nine-patch in the image name refers to the way the image can be resized: 4 corners that are unscaled, 4 edges that are scaled in 1 axis, and the middle one that can be scaled into both axes.
- A Nine-patch image allows resizing that can be used as background or other image size requirements for the target device.

(27) Which dialog boxes are supported by android?

Android supports 4 dialog boxes:

a.) AlertDialog: Alert dialog box supports 0 to 3 buttons and a list of selectable elements which includes check boxes and radio buttons.

b.) ProgressDialog: This dialog box is an extension of AlertDialog and supports adding buttons. It displays a progress wheel or bar.

c.) DatePickerDialog: The user can select the date using this dialog box.

d.) TimePickerDialog: The user can select the time using this dialog box.

(28) What is Dalvik Virtual Machine?

- It is Android's virtual machine.
- It is an interpreter-only virtual machine which executes files in Dalvik Executable (.dex) format. This format is optimized for efficient storage and memory-mappable execution.