A Mobile Engineer at Housecall Pro plays a critical role in empowering home service professionals to manage their businesses seamlessly from the field. Because our users—plumbers, electricians, and HVAC technicians—spend their days on-site rather than behind a desk, the mobile application is the heartbeat of our product suite. Delivering a highly reliable, responsive, and intuitive mobile experience directly impacts their livelihood and business efficiency.

You will work on complex, real-world problems that require a deep understanding of offline-first capabilities, real-time location tracking, scheduling, and payment processing. This is not just about building beautiful user interfaces; it is about engineering robust systems that survive poor network conditions and provide offline data synchronization. As a Mobile Engineer, you will have a direct hand in shaping the architecture and best practices of our mobile platforms, ensuring our applications remain scalable as our user base grows.

The questions below are representative of what you can expect during the Housecall Pro hiring process. They are drawn from actual interview experiences to help you identify patterns and focus areas rather than just memorizing answers.

Coding & Algorithms

This category tests your core problem-solving speed and familiarity with string and array manipulations.

• Write an algorithm to reverse a string in-place.
• How would you optimize a search algorithm for a large localized list of items on a mobile device?

To succeed in the Housecall Pro interview process, you must balance deep technical competence with practical system-level thinking. Preparing effectively means understanding not just how to write code, but why certain architectures and patterns are chosen over others.

Role-Related Knowledge – You must demonstrate a comprehensive grasp of native mobile development (particularly Android and Kotlin or iOS and Swift depending on your focus). Interviewers will drill down into core platform concepts, threading models, and asynchronous programming libraries.

System Design & Architecture – You need to show that you can design clean, decoupled architectures. This includes understanding MVVM or Clean Architecture on the client side, as well as how the client interacts with backend services through APIs, web sockets, and database synchronization.

Problem-Solving & Execution – This is evaluated through live coding and a hands-on take-home project. You must prove that you can write clean, testable code quickly and adapt it dynamically when requirements change during the review process.

Cultural Alignment – Housecall Pro values collaboration, customer-centricity, and ownership. You should be prepared to discuss how you operate within a team, how you handle constructive feedback, and how you ensure your technical decisions align with user needs.

The interview process for a Mobile Engineer at Housecall Pro is designed to evaluate both your theoretical knowledge and your practical execution. It typically begins with an initial HR screen to align on your background and expectations, followed by a technical screen focusing on coding fundamentals and core mobile concepts.

If you pass the initial technical screening, you will be given a homework assignment to build a simple application using a public API. This project serves as the foundation for your final round of interviews. The final round is a comprehensive, multi-stage virtual onsite that includes a presentation of your homework, a live refactoring session, a system design interview, and a conversation with engineering leadership.

The timeline above outlines the typical progression from your first conversation to the final decision. Candidates should expect the entire process to take three to four weeks, depending on how quickly they complete the take-home assignment. Use this visual guide to pace your preparation, ensuring you allocate enough time to polish your take-home project before the presentation round.

Mobile Fundamentals & Technical Theory

This evaluation area focuses heavily on your knowledge of native platform development and computer science basics. Interviewers at Housecall Pro look for a strong conceptual understanding of the frameworks you use daily, testing whether you understand the underlying mechanics or are simply copying patterns.

Be ready to go over:

• Asynchronous Programming – Deeply understand Kotlin Coroutines, Flows (cold vs. hot), and RxJava if applicable.
• State Management – How to manage and propagate UI state reliably without memory leaks.
• Platform Lifecycles – Managing background tasks, configuration changes, and resource constraints on mobile devices.
• Advanced concepts (less common) – Memory profiling, custom view drawing, and fine-tuning local database migrations.

Example questions or scenarios:

• "Explain the difference between a cold flow and a hot flow in Kotlin, and describe a scenario where you would use each."
• "What happens to a running coroutine when the hosting Activity is destroyed, and how do you prevent memory leaks?"
• "Define the exact differences between StateFlow and SharedFlow."

Practical Application & Take-Home Project

Your ability to build, explain, and adapt real code is heavily weighted through a take-home project. You will be asked to implement a simple application using a public API. During the presentation round, you will not only explain your architectural choices but also modify your code live based on new requirements from the interviewers.

Be ready to go over:

• API Integration & Parsing – Clean handling of network requests, error states, and JSON serialization.
• UI & UX Implementation – Building clean, responsive layouts using modern UI frameworks like Jetpack Compose or SwiftUI.
• Live Refactoring – Modifying your completed homework assignment on the fly during the interview to add a new feature or change a data source.
• Advanced concepts (less common) – Implementing local caching strategies or writing unit tests for asynchronous view models.

Example questions or scenarios:

• "Walk us through your architecture choice for this application and explain why you separated your data layer from your UI layer."
• "Now that the app works with this API, how would you modify it to support offline viewing of previously loaded data?"
• "Let's change this list view to support a grid layout with dynamic column counts based on screen orientation."