IONIC Framework Interview Questions & Answers (2025)

The Ionic Framework, an HTML5 platform, empowers developers to create hybrid mobile apps with access to native performance. It's a robust HTML5 SDK emphasizing app aesthetics and UI interaction. While not replacing PhoneGap or JavaScript frameworks, Ionic seamlessly integrates with app frontends. Available under the MIT license, it's ideal for personal and commercial projects.

• Cordova: Cordova is a JavaScript framework that builds apps, which can access the device hardware. Cordova cannot build UI interactions of mobile apps because it uses HTML5, CSS6, Sencha to build UI. However, it complements other web technologies used to develop mobile apps. Cordova is also known as Apache Cordova.
• PhoneGap: PhoneGap is a framework developed by Adobe Systems. It is used for developing mobile applications and can be used by anyone with the knowledge of CSS, HTML, JScript. PhoneGap is a propitiatory version of Apache Cordova and provides extra features apart from the existing Cordova.
• IONIC: IONIC framework is used to build cross-platform mobile apps using web technologies like CSS, HTML. Released in 2013, it was built on top of Angular JS and Apache Cordova.

Ionic Framework was created by Drifty Co. in 2013 and developed by Max Lynch, Ben Sperry, and Adam Bradley.

Run ionic.version command in the console of your web browser to check installed version of IONIC Framework.
Also, Read Javascript interview questions

Check out these popular apps crafted with the Ionic Framework:

1. Pacifica: for Cognitive Behavioral Therapy
2. TD Trading: Stock Trading App
3. Sworkit: Workout and Fitness Plan
4. MarketWatch: Stock Market and Business News
5. ChefSteps: Cooking Tutorials and Tools
6. Nationwide: Insurance and Financial Services
7. JustWatch: Streaming Search Engine
8. Untappd: Social Discovery and Check-in Network
9. National Museum of African American History and Culture
10. Cryptochange: Cryptocurrency Tracker

Services are vital in Ionic for providing app data and performing tasks. Key services like ConnectivityMonitor, SimpleAlert, and GoogleMaps are built-in. When creating a service, remember to import, add a provider, and inject it. Import services where needed, inject them into constructors for access, and add providers to components or globally during app bootstrapping.

Storage in the Ionic Framework provides a convenient method to store key-value pairs and JSON objects. It employs various storage engines, including IndexedDB, WebSQL, and local storage, depending on the platform. There are follollowing storage options in Ionic Framework in below:

1. HTML5 local storage
2. Cookie and session storage
3. IndexedDB
4. WebSQL
5. PouchDB
6. Web service/API storage
7. Cordova storage

The Ionic framework offers several advantages and disadvantages:

Advantages:

1. Single source for multiple platforms, mainly Android and iOS.
2. Developed in familiar languages like HTML, CSS, and JS.
3. Utilizes Angular, enhancing development efficiency.
4. Free and regarded as a top open-source solution for hybrid app development.

Disadvantages:

1. Performance gap compared to native apps.
2. Security may be weaker than native apps.
3. Ionic apps may lack certain native functions, requiring plugin development.

The superiority of Ionic 2 over Ionic 1 stems from several key features:

1. Ionic 2 utilizes classes instead of controllers.
2. Each component in Ionic 2 has its own folder and class file.
3. Automated generation of pages, providers, tabs, pipes, components, and directives.
4. Emphasis on a more native navigation approach.
5. Ionic 2 employs standard JavaScript.

The latest iteration of the Ionic Framework is version 4.0, launched on January 23, 2019. Ionic leverages Angular 6 or higher for development, enabling the creation of native-like mobile apps using web technologies. Its primary emphasis lies in enhancing the look, feel, and user interface of applications.

Observables are something that are not specific to Ionic or Angular and are provided by the RxJS library. Observables are almost similar to the promises but can do a lot more. It can deal with multiple values at a time rather than just resolving one value. You can even subscribe to an observable to manipulate the data which is associated with it. Observables are considered to be “lazy”, i.e. they won’t get executed until and unless they are subscribed to.

Various operations can be applied to the observables for modifying it and returning a new one. You can even create your own observable. The observable patterns are combined into one with the help of subject which is preferred for simple implementations.

You can Parse JSON in Ionic with the following steps:

• CREATE TABLE users( user_id int AUTO_INCREMENT PRIMARY KEY, username varchar(50)
• CREATE TABLE feed( feed_id int PRIMARY KEY AUTO_INCREMENT
• <ion-header> <ion-navbar>
• /* Time Ago */ $npm install --save angular2-moment
• $ cordova platform add ios. $ ionic build ios
• $ cordovaplatform add android. $ ionic build android

To open a download link within an Ionic inAppBrowser, set the target attribute of the anchor tag to _system. This ensures the link opens in the device's default browser, allowing for downloads.

To rename an Ionic app from "HelloCordova" to "custom", navigate to the app's root directory. Then, rename the folder containing the app's source code and update references to it in configuration files and code files.

To update Cordova plugins, use the cordova plugin update command followed by the plugin's name or ID. This command fetches and installs the latest version of the specified plugin.

Use the following command to update Cordova plugins.

npm install -g cordova-check-plugins
cordova-check-plugins --update=auto

You can use the non-native plugin in Ionic by first installing the ionic Cordova plugin add and then adding var session = new cordova.plugins.phonertc.

To get a selected value from a select in Ionic, you can access the Ionic select by using a standard element. You must take care that the select component always used with the child element, therefore if the does not have a value attribute, then its text will be used as the value.

To create a custom initial splash screen in Ionic:

1. Craft a splash screen transitioning smoothly to a fake one, like a solid color.
2. Disable auto-hide for the splash screen.
3. After app loading, initiate the animated fake splash screen.
4. Conceal the actual splash screen.
5. Dismiss the fake splash screen after a specified time.

To convert a base64 image to a blob image in Ionic, you can use the atob() function to decode the base64 string into a binary string, then create a Blob object from it. Here's an example:

// Convert base64 image to blob image

const base64String = 'your base64 image string';

const byteCharacters = atob(base64String);

const byteNumbers = new Array(byteCharacters.length);

for (let i = 0; i < byteCharacters.length; i++) {

    byteNumbers[i] = byteCharacters.charCodeAt(i);

}

const byteArray = new Uint8Array(byteNumbers);

const blob = new Blob([byteArray], {type: 'image/jpeg'});

Now you have the image data in a Blob object, which you can use as needed in your Ionic app.

The default activity class name from AndroidManifest.xml typically refers to the main activity of an Android application, which is often named "MainActivity" by convention.

Frontpage is the default activity name from AndriodManifest.xml

Use Html5 maxlength property to add maxLength on ion-input.

Example

<ion-content padding>
  <ion-list>
    <ion-item>
      <ion-label color="primary" stacked>Stacked Label</ion-label>
      <ion-input type="text" maxlength="4" placeholder="Password Input"></ion-input>
    </ion-item>
  </ion-list>
</ion-content>

Add no-bounce property in <ion-content> element to disable content scrolling in IONIC.

Example

<ion-content no-bounce></ion-content>

LocalStorage, IndexedDB or SQLite Plugin, websql, pouchdb, SessionStorage are few storage options available in Ionic Framework.

Ionic 4 introduces several remarkable features enhancing cross-app development:

1. Web Components
2. Capacitor
3. Stencil (web component compiler)
4. ion-Backdrop
5. ion-Picker
6. ion-Ripple Effect
7. ion-Route
8. Color Changes
9. Lazy Loading
10. CSS Variables
11. Ionic Native 5

Ionic Framework was developed by Max Lynch, Ben Sperry and Adam Bradley of Drifty Co. in 2013.

Difference between HTML5, native and a hybrid app are

• Native app: A native application is basically a software or a program that is basically designed to perform a specific task on a specific platform.
• Hybrid app: Hybrid apps are nothing but it is quite similar to the native apps. The only reason here is that it can be downloaded from the platform app store. The functions that it can perform are quite similar to the native apps.
• HTML5 apps: The HTML5 apps can be used elsewhere in any platform of any mobile device.

The Iconic codes are written in HTML, Javascript, and CSS. Ionic also uses AngularJS for a lot of the core functionality of the framework.

Web Views are full screen web browser which iss capable to render apps made with web technologies like HTML, Javascript, css. Ionic uses web technologies to create hybrid mobile apps.