Mobile System Design

By the author of the Mobile System Design and Swift in Depth books

Ace Your Mobile System Design Interview

Use the Quick Reference Cheat Sheet to prepare fast and land that job, then go deeper with the full book bundle.

Only have a few days? Start here

If you're short on time, the Quick Reference Cheat Sheet is your fastest way to prep. It includes preparation checklists, high-signal interview questions, example answers, prototyping and diagram tips — all designed to help you stand out.

It’s included with the full book package; your complete system design reference, with 500+ pages of deeper patterns, strategies, and architecture thinking for real-world apps.

Want to go deeper? Learn at your own pace.

Quick Reference Cheat Sheet

Used by devs at Facebook, NYT, and companies around the world.

Start Interview Prep — $79

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It has helped me crack some of the most difficult System Design interviews.

It's even helping in my current role where I'm heading the mobile division.

— @_thatabishek

Why I Made This Guide

Tjeerd in 't Veen
Most system design advice is backend-focused, which is not how mobile teams work. I built this guide to help engineers cut through complexity and communicate clearly under pressure.
— Tjeerd in ’t Veen
Author of Mobile System Design and Swift in Depth
Former Staff Engineer at Twitter, Mobile Tech Lead at ING

Why Interviews Are So Challenging

You know how to build great apps. But in interviews? Explaining architecture, tradeoffs, and flows under pressure is a different skill.

You’re expected to:

  • Break down real-world systems
  • Work with incomplete or ambiguous requirements
  • Reason through tradeoffs, edge cases, and failures
  • Show technical depth and communication skills

Most developers aren’t used to articulating high-level architecture decisions. And for some, the challenge runs deeper, they’ve never had to make those decisions at a deep level. That’s why design interviews are tough, and why targeted prep can make a huge difference.

What Interviewers Actually Look For

Interviewers want to see how you think. They’re looking for clarity, structure, and decision-making under pressure.

You’ll stand out if you can:

  • Confidently explain system architecture
  • Walk through user flows and edge cases like a pro
  • Understand what interviewers are really evaluating
  • Internalize patterns that scale across teams and platforms

Whether you're targeting a senior role or just want to stop blanking during system questions, this material gives you a clear structure and repeatable approach.



What Readers Are Saying

These are real comments from developers who’ve read Mobile System Design — whether for learning, interviews, or improving architecture on the job.

A Complete Toolkit to Help You Stand Out

Everything you need to prep fast and grow long-term.

All books and materials included

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Includes the Quick Reference Cheat Sheet, your go-to interview prep tool. Instant access. Free updates.