Mobile Application Developer Interview Questions And Answers

If you’ve chosen App Developing as a career, chances are you’re always in the know of the latest apps. The recruiting manager will expect you are always trying out and testing different apps and you have a solid criteria about what’s well done and what should improve. Be sure you take some of your favorite apps on your smartphone, be prepared to talk about them from functionality and developing context.

This is by no means an unreasonable question to ask in any interview. In fact, mobile app developers should be more than willing to provide examples of their previous work.

Test drive the apps they’ve developed in the past. It’ll give you an idea of what they’ve done and if it’s aligned with what you’re asking for.

Mobile app developers should give you a tour of the apps on their phone, or happily provide links to the apps on the App Store or Google Play store. They should go into detail about their involvement and how it directly relates to what you’re looking for.

Not all mobile app developers will have built an app from scratch, but rather worked on different aspects of the app.

Once an app has been developed and is thoroughly tested, it’s time to launch. Your app developer should have experience submitting the app to various app stores.

The submission process is a long one, and it can be frustrating. Your developer should know how the process works and guide you along the way.

The app should be submitted under your name, not under your mobile app developer’s name. The app store must know who is responsible for the app in the event that you are no longer in communication with the mobile app developer you hired. Without it, new versions of the app cannot be submitted to the store, and you’ll be forced to release a brand new app under a different account or name.

Native or responsive is usually the first question people ask when they find the terminology unfamiliar. What is the difference from a design perspective?

Mobile apps can be developed natively or as hybrid apps, while mobile-friendly websites can be developed as adaptive or responsive. The basic design process behind all of them is more or less the same. The only thing we need to consider when designing for mobile is that we have a specific set of rules we need to follow. Apple has its own, and so does Google.

When you’re designing for iOS or Android, the underlying process is the same. First, we do research that will outline best practices and show us what we can do on a certain platform and what not. Basically, research helps us we learn restrictions and take advantage of possibilities a given field.

Designers are likely to work on both native app and responsive web designs. Native apps are important because we want the user to have them on their dashboard, and this way we want to help users in their everyday activities. Some native apps can work offline while others can’t.

Responsive web design is important for SEO and Google indexing. So, if we want to have your project well-ranked on Google, you definitely go for a mobile-friendly responsive design.

As technology advances, designers have to deal with fewer and fewer restrictions, and can employ a variety of new solutions to enhance user experience. The new iOS 3D Touch gesture poses some physical challenges for users. Designers should take advantage of it to enhance user experience by making pages previewable and supporting quick access to frequently used features.

There are two main actions supported for now: Peek and Pop.

Peek and Pop allow apps to let users preview content and perform related actions within the app, before deciding if they want to view the full content. For instance, peeking can be used to provide live, content-rich previews. Ideally, peeking gives enough information about an item to augment the current task or helps you decide whether or not to fully engage the item. For example, preview a link in an email before deciding to open it in Safari or share it with friends. Peeking is often used in tables to view detailed row information before the row is selected.

3D Touch is an emerging technology, and is not supported by pre-2015 Apple devices. However, as older devices are phased out, it will be available on most, if not all, Apple platforms. In addition, Force Touch technology is coming to Android devices as well, and other platforms are bound to follow.

Tabs are one of the most frequently used components of mobile UIs, and for good reason.

They allow users to quickly move between a small number of equally important panes and bring a real-world element to the web and mobile applications. When implemented correctly, tabs can be an excellent user interface control element that can greatly improve usability.

They are considered to be very intuitive and easy to use. Well-designed tabs clearly indicate the user’s current location using a different visual appearance that sets active tabs apart from the others.

If you need a practical example, look no further than your desktop browser.

User interface and user experience are key to successful mobile applications, so expect a lot of UI/UX questions. State your opinions and tips on getting the most out of the mobile’s interface. You may point out which apps you think have a great UI and which ones don’t. Also, some recruiters may ask you to quickly draw a scheme of an interface –be prepared to do it.

The features and functionality within the app are going to drive the app’s operations. Having said that, it should also be pleasing to the eye, easy to use from a navigation perspective, and offer a unique experience.

The app you build must stand apart from the rest because there is heavy competition.

You want your app to be memorable.

Mobile app design isn’t as simple as choosing pretty colours and images to use. The right design will make all the difference. Take a close look at the developer’s portfolio to see if creativity has been built into the app, and if the user interface and user experience is something you enjoy.

Remember we mentioned the part about not being in communication with your mobile app developer? If all goes well, you will have hired a professional mobile app developer with whom you can establish a professional working relationship. More importantly, they will be there for you long after the app is sent to the app store.

Keeping users engaged, keeping up with bug fixes and updating app versions is part of the maintenance process. No one knows the ins and outs of your app better than your mobile app developer.

Ask them how maintenance support programs are structured, and how they will address changes to the app as needed. Also, find out how much it costs. Most developers will charge by the hour.

Cards are fast becoming one of the best design patterns for mobile devices. They collect individual pieces of content aggregated together into one experience.

We are currently witnessing a re-architecture of the web, away from pages and destinations, towards completely personalized experiences built on an aggregation of many individual pieces of content. This is a result of the rise of mobile technology, which resulted in billions of new connected devices, using different resolutions, pixel densities, and form-factors.

The idea behind cards is to show the user only relevant information at the right time. This way user focuses solely on the most important message, while most clutter is removed.

The best time to use cards would be when we need to show a particular bit information, deemed important to the user at a given time. While the card approach could be used all the time, the way Twitter separates tweets one from another, this is not always practical.

There are many services and websites already using the card system to display information. This way they visually separate or highlight information.

Input fields are a very important aspect of mobile design. We tend to take them for granted, especially when designing small websites or mobile apps.

When we need to design a corporate website where we have more than one contact form, then we should reconsider and reimagine these small elements. The whole point of doing this makes them invisible to the end-user, allowing users to focus on more important things. We don’t want our users to leave at a crucial point in their journey, when they need to input information or maybe even make a purchase. This usually happens on e-commerce websites when the user is required to fill in too many fields in order to complete the transaction. The trend is to streamline the process, and big players are getting involved with mobile wallet solutions as well.

For mobile design, it is important to provide clear, always visible labels for each input field. Clear labels make users feel more confident that they understand information in the right way, promting them to take action.

Data comes in many formats. Of course, we think that you should always try to design input fields in a way that resembles how users typically enter information. For instance, the phone number field can be auto-formatted. This eliminates any formatting ambiguity the customer may have had.

Based on user-research, annoying notifications are the primary reason why people uninstall mobile apps (71% of respondents in one recent survey).

But still, push notification are a feature which keeps an app alive. In other words, notifications are powerful tools for businesses to communicate directly with users and deliver the right message at the right time and place in order to promote engagement. So it’s really important to consider how these elements are designed.

It’s important that the messages are clear and understandable. No matter what the content of the notification is, make sure it speaks the same language as your users, literally and figuratively. Users, regardless of frequency, appreciate content that is directly related to their personal interests.

Timing is the second most important thing when we consider making push notification. Also, solution could be sending a notification out at a reasonable time that would be most effective to your users, unless it’s critical to inform them of something happening right now. In general, mobile usage peaks between 6pm — 10pm.

This is where you show off your work and talk about your experience. Point out the role you played in the development of each project and the difficulties you encountered when creating it. If you haven’t yet developed any professional app yet, you can show off the apps you have developed on your own or as school practices. It is a great idea to create an open source app before you apply for jobs.

Communication is a critical component of any project. Since you’ll be working very closely with your mobile app developer, you want to understand how you will be working together (i.e. how often will you be communicating with him or her).

Most developers use project management programs to list task, mark them when they’re completed, and send out progress notifications. Basecamp, Jira and Asana are examples of project management programs that are widely used today.

Ask the developer if they use a program like this. If they do, it’s a solid indication that they know how to keep track of deliverables, use the tool to communicate with key stakeholders, and track the progress every step of the way.

You should also identify how often you’ll want to speak with the developer. Will you schedule a weekly meeting set for a specific time and date?

Iconography is a visual language used to represent functionality or content. Icons are used when we don’t have enough space to display textual content. Therefore, icons are meant to be simple visual elements that are recognized and understood immediately.

In practice, we will encounter both version of these icons. They can appear outlined or filled, but the whole icon set needs to be consistent and employ the same stroke. However, this is something that is more related to visual design. When it comes to UX, one thing is sure. If we use the outlined icons for the normal state, then we should probably use the filled icon for the active state of the button. It’s important to indicate which section is currently active by highlighting the icon in a specific way. Although we could change the color of the outline, this approach is not ideal when we are dealing with a light background, so it’s better to use the filled/outline approach. This makes recognition of active tabs and controls more straightforward. Icons at the end are here to serve as navigation to other section of the app.

Due to the fact that mobile design is constrained by the small size of mobile devices and their displays, it’s of vital importance that we present the information properly, and adequately prioritize content. It is very important to make sure this is done at this stage, before we proceed to mockup design, because that’s a matter of UX rather than UI design.

It’s also important to decide which information we provide first and which one will remain hidden. In order avoid hiding content, we can use different patterns like tabs, filters, and so on, while still providing the user with the most important information at the time. It’s a bad practice to use hamburger menu even though sometimes we are forced to use it due to the massive amount of data that needs to be displayed. Based on research, we can conclude that the hamburger icon easily gets “lost” in the design, because many users tend to start scrolling immediately. It’s in our nature to scroll and that why it’s important to make sure everything important is presented to the user at a glance.

According to a study by Nielsen/Norman Group, a global leader in user experience research, training, and consulting, hidden navigation patterns (like hamburger menus) decrease content discoverability by 21% and increase the amount of time it takes to actually use navigation by 2 seconds on average.

Input fields are a very important aspect of mobile design. We tend to take them for granted, especially when designing small websites or mobile apps.

When we need to design a corporate website where we have more than one contact form, then we should reconsider and reimagine these small elements. The whole point of doing this makes them invisible to the end-user, allowing users to focus on more important things. We don’t want our users to leave at a crucial point in their journey, when they need to input information or maybe even make a purchase. This usually happens on e-commerce websites when the user is required to fill in too many fields in order to complete the transaction. The trend is to streamline the process, and big players are getting involved with mobile wallet solutions as well.

For mobile design, it is important to provide clear, always visible labels for each input field. Clear labels make users feel more confident that they understand information in the right way, promting them to take action.

Data comes in many formats. Of course, we think that you should always try to design input fields in a way that resembles how users typically enter information. For instance, the phone number field can be auto-formatted. This eliminates any formatting ambiguity the customer may have had.

Different screen sizes and resolutions, variable connection speeds, battery consume, memory limitations… mention the problems inherent to mobile devices and go technical, show the hiring manager you truly know how to manage them.

You can’t expect a mobile app developer to successfully build your app without understanding what it is you do and how the app will make a difference.

A potential candidate won’t have all the answers, but what you can do is take time from the interview process to educate them about your bottom line, your mission and goals for the app. If a developer takes an interest in what you do, it’s a positive sign. More importantly, they should have an interest in using the app itself.

A developer who has worked on apps of similar functionality, or who has clients in the same industry may be a positive fit. They’ll already have an understanding of your business model and will know what it will take to achieve mobile app success.

User onboarding is the process of increasing the likelihood that new users will successfully adopt your product.

When launching a product, you need to spend a lot of time and resources to attract a sufficient number of users. There are a variety of means to attract users to your app, including advertising, referral programs, public relations, and content marketing. But when people finally download the app, they sometimes feel abandoned or let down. Therefore, you must do a good job at showing users why they need your app and how they should use it.

Onboarding can sometimes be an integral part of the app, where we show the user how to behave within the app. This dive in effect is especially useful if we incorporated some new features that might be unfamiliar to our users. Tooltips can also be used to show them how things work.

The same approach can be used when we have complex systems. With tooltips we can explain why some things are there or why others are not. It’s something like a guided tour of your app, where hints are only triggered when the user reaches an appropriate point in their experience. Thus, hints may appear in different orders for different users and actions.

When users depend on scrolling as their prime method of exploring data, it may compel the user to spend more time on your web page, thus increasing engagement. With the popularity of social media, massive amounts of data are being consumed; infinite scrolling offers an efficient way to browse that ocean of information without having to wait for pages to preload.

Users tend to have better experiences with scrolling than clicking/tapping. Gesture controls on mobile devices have made scrolling intuitive and easy to use. As a result, the users enjoy a truly responsive experience, regardless of what type of device they’re using. The biggest challenge is to maintain good performance in an application or website with infinite scrolling. If we see that the app will use too many resources because of size and volume of images or other types of content, then we need to make sure we try out an alternative approach.

Pagination is a user interface pattern that divides content into separate pages.

Pagination is good when the user is searching for something specific within listed content, not just scanning and consuming the flow of information. Furthermore, the user gets a sense of control. Infinite scrolling is like an endless game, while pagination allows us to visually sort different items. This means that if the user was searching for something on a website then he will quite easily find the necessary information on a paginated interface. Pagination is good for e-commerce sites and apps. When users shop online, they want to be able to come back to the place they left off and continue their shopping.

So basically, both approaches have their pros and cons. Which one should we choose?

There are only a few instances where infinite scrolling is effective. It’s best suited for sites and apps that boast lots of user-generated content (Twitter, Facebook) or visual content (Pinterest, Instagram).

Displaying faceted-search controls on mobile devices in a ‘tray’ overlay is a new and effective way of displaying both results and filters on relatively small mobile screens.

Faceted search lets users refine a set of results by applying filters that comprehensively describe the search space. The ability to narrow down searches is invaluable for users who need to find something specific within a large content set. This type of search has become common for e-commerce/m-commerce and travel websites, as well as many different types of document and media collections.

A faceted system includes two critical elements:

Simple controls to construct sophisticated searches - providing familiar controls like drop-down menus and checkboxes with natural-language labels. This allows ordinary users to narrow down a large set of results to a smaller set that meets their exact criteria, without any knowledge of Boolean logic or query syntax.

Simultaneous display of the facet controls and the results - Showing both the filters and the results at the same time makes it easier for users to understand the relationship between the two; ideally, this is reinforced by dynamically updating the results set as soon as the user selects filter criteria.

Pokemon Go changed the rules of the game and created a new trend in mobile design and gaming. The combination of Augmented Reality (AR) and flexibility provided by smartphone platforms helped create a whole new user experience. These emerging technologies will bring monumental changes to digital product design.

The gaps between smart devices (smartphones, tablets, laptops, wearables) are being blurred with each consecutive product generation. Rapidly evolving hardware is bringing AR closer to mainstream users, even though the concept has been around for a while. There are many reasons why the interface will evolve. Designers are no longer limited by technology, their biggest limitation today is their own creativity. It is also important that many of these emerging technologies are reasonably priced, or seamlessly integrated in new devices at no extra cost to the user.

The design process in the future will change. For example, in order to make an interface for VR we need specialist skills, and we need to create UIs in 3D. In addition to designing 3D assets, designers will also have to master certain skills, for example learn some Unity basics, or employ 3D design software.

Animation has long been used as an eye-catching element that helps differentiate an app from its competitors.

Now, however, more designers are incorporating animation as a functional element that enhances the user experience, to simulate the appearance of interacting with a real object.

Animation is no longer just for games. It also illuminates navigation: Think of a button that toggles a panel of otherwise hidden content, such as a menu. Closing the panel shrinks the menu, where it disappears back into the button. Other examples include zooming content or providing feedback to confirm a user’s action.

Functional animation makes app experiences more dynamic and provides a more direct visualization of the user’s actions. As smartphones become more advanced, designers are adding HTML5 animation and parallax design to mobile apps to bring a new level of richness and excitement to the mobile user experience.

Before you begin interviewing potential candidates, create a wish list of which features your app must have, and which are nice to have. A list gives your potential mobile app developer an exact idea of what you’re looking for.

Once you have that list, ask the developer what functionalities and features they have experience developing. If your app requires very specific integrations that need to be included, then you’ll need to work with a developer with experience.

An experienced developer may still be capable of learning the functionality building you need; speak with them one-on-one to learn more.