Top 10 mobile app development interview questions answered

As a mobile app developer, you’re likely asked to answer questions about your experience in the field. Also, a quick search on Google with the query “Mobile App Development Questions” will return millions of results.
But are those all relevant to your interview? If not, how can you find the most frequently asked mobile app development interview questions?
To help you out, I’ve chosen a few key questions to consider if you’re interviewing for a job or a recruiter looking to hire the best candidate for the job in 2022. You can find the 10 common interview questions here, which cover areas such as development tools and how to handle errors while building applications.
These questions can be used as an interview approach or as a way to evaluate candidates’ knowledge and skills. For best results, make sure to answer each question yourself before you look at the answers. 

 So let’s get started!

1. Tell us about your experience in mobile app development

You may have worked on a project or two, but how much experience do you have in the field? Have you been developing mobile apps for years?
If so, what kind of projects did you work on, and what were some of the challenges involved in those projects? Have you ever had to build an app from scratch, and if so, what was your process like? How long did it take? What tools did you use during this process? How would your experience help our company improve its product line by using a more efficient development approach than they currently do?

2. What are your favorite tools for mobile app development, and why?

• Build tools: I use the Xcode environment for building apps and the Android SDK for developing native Android applications.
• Testing tools: I rely on a combination of unit testing, integration testing, and functional testing to ensure that my apps are error-free before they’re deployed.
• Debugging tools: When you’re developing an app, it’s important to be able to find and fix bugs quickly so that you can get back to work as soon as possible—which is why it’s critical that your development team has access to good debugging techniques like code traceability analysis (CTA).

3. What is the difference between Flutter and React Native?

Flutter is a new cross-platform mobile app development SDK from Google, while React Native is a framework for building native apps with Javascript and React.
Flutter uses Dart, which is a programming language developed by Google. It’s designed to be fast, flexible, and easy to use. Dart was originally created as part of Google’s internal toolkit but has since been open-sourced under the Apache License 2.0 (the same license used by open-source projects like Linux).

4. How can you reduce the size of an app build?

• Code splitting
  Code splitting is a technique that allows you to split your application into multiple components, each of which can run on a separate thread. It reduces the size of your app and improves performance by allowing you to load only what you need when it’s needed. In this way, code minification can help reduce the size of your build because it removes unnecessary code from production builds.

• Lazy loading
  Lazy loading is similar to lazy routing in that it loads content only when it’s needed by an application user or visitor, rather than all at once upfront before they visit any pages within an app or website (the opposite behavior from pull-based architectures). This approach has two benefits:

Firstly, it reduces initial download times, so users don’t have to wait around forever while waiting for resources like images, media files, etc.;

Secondly, if there are no delays, then users will see faster page loads, so overall interaction becomes smoother without having those annoying pauses.

• Optimize the app’s resources.
  Any resource, whether used or not, uses memory. Memory should be used efficiently, and resources should only be used when necessary. The resolution of the image should be taken into consideration before making a decision.

• Optimize libraries
  It’s best to remove any items you don’t need from a large library if its license allows it and if you don’t need them. You can use Proguard to accomplish this, although it sometimes struggles to remove significant internal dependencies.

• Optimize Images
  Compressing images without compromising the image quality will make your app run faster and smoother. In this way, the app size will also be reduced, and more features can be added.

5. How do you measure an app’s performance?

The most important performance indicator is how long it takes your app to load. You should measure the time from when a user clicks on the button for an app to launch until they see its interface, or even more importantly, until they start seeing data. This can be done using tools like Firebase Performance Monitoring and Google Analytics.
You also need to consider what happens when users close their phones; if you’re using push notifications or push-to-talk functionality in your app, this will have an impact on the performance of your application as well as battery drain and bandwidth usage.

Other key performance indicators include:

• Number of users visiting pages per second (PPS)
• Each page view determines how many pages are loaded per second.
• UX and performance metrics
• Revenue metrics
• The complexity or crash reports

6. How do you handle errors in Flutter while building an application?

In response to the question, “How do you handle errors in Flutter while building an application?” It’s important to understand that Flutter has a rich set of tools to help you debug your app.
You can use the debugger to step through your code and see how each line of code executes, as well as where exceptions are being raised. The debugger also allows you to specify breakpoints at specific points in your application’s flow so that if an exception is raised during execution, then that particular line will be paused at that point—you can then examine variables and look at values before continuing with execution.

7. What is the HTTP/2 protocol, and how does it relate to Android apps?

HTTP/2 is the latest version of HTTP, and it’s faster and more efficient than HTTP/1.1. It’s supported by all major browsers, including Chrome and Firefox, as well as Android devices (including both Android 7 Nougat and 8 Oreo). In fact, it’s used to build secure apps that are compatible with a variety of mobile operating systems (iOS 10 and above, Windows 10 and above, and MacOS High Sierra).

8. Which type of data is most suitable for storing in shared preferences?

You will be asked to design a data model for your app. The following schema shows an example of how you can use shared preferences to store small amounts of data:

• An order object would have a unique identifier, such as “1234567890,” and the customer’s name and address information.

A product object would have its type (book or CD), price, quantity in stock, and product code.

9. What are the steps you will take to make your mobile app secure for both iOS and Android platforms?

There are many steps you can take to make your mobile app more secure for both iOS and Android platforms. Some of these include:

• Use a VPN that encrypts all data passing through it, making it nearly impossible for hackers to steal information. This is especially important if you’re using public Wi-Fi or cellular networks because they can be used by hackers to intercept sensitive information like passwords or credit card numbers while they’re being transmitted over the airwaves via Wi-Fi hotspots at airports, cafes, and other places where people go online often with their smartphones or tablets.
• Use a firewall on your computer or laptop so that no one else can access any data stored on them without permission from the owner first (this would include malware).

10. What type of testing does a developer usually perform, and what is its purpose?

You should be able to answer this question with a high degree of confidence.
There are several types of testing that can be performed on mobile apps, including functional testing, performance testing, security testing, and load testing.
Functionality refers to the way an application works when it’s being used by end users; performance refers to how well the app runs under different conditions; security refers to how secure your app is from hackers looking for vulnerabilities in its design; and load-testing measures how much traffic you’ll get from users on different devices at different times of the day, weeknights, weekends, etc., which helps predict how many customers will sign up for an app regardless if they’re abusive or not!

Conclusion

These are some interview questions you can practice in case you need to prepare for an interview quickly. These questions will also help hiring managers evaluate candidates based on their knowledge and skills.
The interview process is an important one, so it is important to prepare well before going in for your interview. However, as a newcomer, interviewing for a job as a mobile app developer can be intimidating. This is especially true if you haven’t been actively learning. The previously mentioned QNAs, as well as the series of interview questions, are the most important ones to look for. 

I wish you all the best!