A bunch of phonegap interview questions for Hybrid application developers.
1.What is PhoneGap ?
PhoneGap is an open source solution for building cross-platform mobile apps with standards-based Web technologies like HTML, CSS and JavaScript. It is a wrapper used for native packaging of mobile web application which is used to build cross platform mobile Application.
2.What is the PhoneGap architecture.
PhoneGap has a plugin-based architecture. Each device-specific feature is a plugin, which consists of javascript and native sides.Javascript side should be as cross-platform as possible, whereas native side can be implemented only once, for 1 device. Nevertheless built-in plugins are developed for all of the most popular platforms, so no need to reinvent the wheel.
This architecture, together with open source code, not only allows a developer to fix their bugs, but also allows them to tweak their plugins for as per requirements. Also, a developer can build his own plugin, and support any platform of his choice.
3.Why we consider phonegap for mobile application development?
We use PhoneGap because it allows them to have a common codebase for all their application code. It doesn’t force developers to reinvent the wheel every time they move from platform to platform.
4.How does phoneGap simplifies mobile development?
Building applications for each device–iPhone, Android, Windows Mobile and more–requires different frameworks and languages.PhoneGap will use standards-based web technologies to bridge web applications and mobile devices. PhoneGap apps are standards compliant, they’re future-proofed to work with browsers as they evolve.
PhoneGap is an open source implementation of open standards. That means developers and companies can use PhoneGap for mobile applications that are free, commercial, open source, or any combination of these.
5.what are the platforms that PhoneGap supports ?
The platforms phone gap supports are
iphone/iphone 3G and Higher
Blackberry os 5.x and Newer
Android
Web OS
Tizen
Windows Phone 7
Symbian
Bada
6. What are the PhoneGap Features?
It allows you to package your mobile web application code and resources into a binary app and ready to distribute to Apple, Android, Palm, Symbian, and BlackBerry devices.
It is not only the purpose of PhoneGap to distribute the web application to application store.
It is also providing the feature to access the device hardware from web application.
7. Advantages of PhoneGap ?
One codebase can be maintained for multiple platforms
Reuse existing web developer skills
Faster development
Based on open standards
8. What is PhoneGap Cordova ?
Mobile market is huge with bunch of opportunities. At the same time it is really painful experience for the developers to make an application reach to the wider audience.
There are multiple platforms like android, iPhone, Blackberry, windows comes with lot different capabilities. Every platform uses different programming language syntax and different distribution process.
As the programming platforms are different, developing an application requires putting the separate development effort for different platforms.
9. What is the difference between PhoneGap and Cordova?
PhoneGap was donated to the Apache Software Foundation (ASF) under the name Apache Cordova. Through the ASF, future PhoneGap development will ensure open stewardship of the project. It will remain free and open source under the Apache License, Version 2.0.
PhoneGap is an open source distribution of Cordova. Think about Cordova’s relationship to PhoneGap like WebKit’s relationship to Safari or Chrome.
10. What is PhoneGap Build, and how is it different from PhoneGap framework?
PhoneGap is a mobile application development framework, based upon the open source Apache Cordova project.It allows you to write an app once with HTML, CSS and JavaScript, and then deploy it to a wide range of mobile devices without losing the features of a native app.
PhoneGap Build is a cloud-based service built on top of the PhoneGap framework.
It allows you to easily build those same mobile apps in the cloud. Learn more about PhoneGap Build and try it out for free!
11. What is a hybrid app?
A hybrid application is one that has features of both a web application and a native application. Certain features, such as Image Capture, NFC or Android OpenAccessory, may be implemented natively since there is currently no way to do this in JavaScript. But the application logic and the UI are implemented using web technologies to allow for a consistent and unique user experience across devices.
12. what are the PhoneGap events
The phone gap events are listed below
deviceready
pause
resume
online
offline
backbutton
batterycritical
batterylow
batterystatus
menubutton
searchbutton
startcallbutton
endcallbutton
volumedownbutton
volumeupbutton
13. What does PhoneGap plugin consist of? What are the files required to create your own PhoneGap plugin for IOS?
PhoneGap plugin contains two files
JavaScript file that defines the function for accessing the native hooks
Implementation files written in the native language to co-ordinate with native phone features
To create your own PhoneGap plugins, you have to
Make a new directory in your ${PROJECT_DIR}/plugins directory
Make a JavaScript file within that new directory
Make a new Objective-C class that extends the PhoneGap command class and also in the new directory
14. Explain how you can upgrade PhoneGap?
To upgrade PhoneGap in Mac and Linux
$ sudo npm install –g phonegap
For Windows:
C:\> npm install –g phonegap
15. What are the limitation of PhoneGap?
As the front-end uses JavaScript it does have some limitation
Data processing: Compare to JavaScript native language is much faster
Back-ground processing: Large number of application depends on background thread while PhoneGap API are built using JavaScript which does not support multi-threaded and hence does not support back ground processing
Advanced graphics: Apps that use advanced graphics can be accessed explicitly by third party libraries, which can be best done natively
Complex business logic: Number of complex business app can be accessed better with a native code
Access advanced native functionality: Number of native API’s are not supported by PhoneGap’s API
16. What are the storage option does PhoneGap can access?
Memory-store.js (MemoryStore)
Is-store.js (LocalStorageStore)
Websql-store.js (WebSqlStore)
