From the author of The Pragmatic Engineer blog and The Tech Resume Inside Out

Building Mobile Apps at Scale: 33 Engineering Challenges

Building mobile applications at scale are just as challenging as architecting and operating distributed systems. I know - I've done both for years at Uber. There tends to be little understanding of these problems until coming across them - and even fewer resources to go about addressing them.

The missing guide for building large, iOS, and Android native apps -with the challenges and common solutions across the industry.

Launching March 2021. Access the beta today for free - thanks to sponsors Bitrise and Bugsnag.

Building Mobile Apps at Scale

Most organizations don't "get" the complexity with mobile. The book started my observation on how even "mobile-first" companies seem "backend-heavy" with their focus, with little appreciation or empathy for mobile complexity. Every mobile engineer or manager I've mentioned this to nodded, and I started writing down engineering challenges unique to native mobile engineering on large apps or large teams.

Most mobile engineers are unaware of key challenges at scale - before hitting them. I've been collecting various challenges specific to mobile for over a year - building on my 4 years experience at Uber, and 10 years of building native apps. I had a pretty complete list with 24 challenges. When I shared the draft with over 20 mobile experts, they pointed out several other areas that were common across large apps. If you are building native apps, you're more than likely to find new insights.

Buy vs build for common challenges? Mobile build systems, experimentation and feature flags, crash reporting, manual testing and several other problems you'll need to solve for regardless of your app size - what tools and solutions are commonly used in the industry? The book points to resources worth exploring.

Book Contents

Challenges Due to the Nature of Mobile Applications

Mobile comes with problem areas that either don't exist or are fundamentally different on backend and web. Deeplinking, push notifications, app crashes, accessilbity, offline support, fragmentation and others.

Challenges due to large and complex apps & large teams

As the app and team grows, previously small issues become too large to ignore. Navigation architecture, localization, testing, build times, architecting to avoid conficts and more.

Challenges When Stepping Up Your Game

When you aim for world-class apps, you need to keep ahead. Experimentation, feature flags, monitoring and alerting, data migrations and other areas.

Who This Book Is For

Written for mobile engineers, engineering managers and those who want to build empathy on why it's challenging to build mobile at scale.

Native Mobile Engineers

You have experience building native iOS or Android apps. You're keen to learn about approaches and industry practices - ones you can put in place in your current project or app. This resource is also an ideal one to get validation on your approaches, comparing it to how others in the industry solve problems you have.

Engineering Leads and Managers

You directly or indirectly manage mobile engineers and want to stay up to date on where the industry currently is. Several managers found the contents useful for better decision making, and in helping their teams make pragmatic mobile engineering decisions.

Stakeholders and Engineers working with Mobile Engineers

You work with mobile teams or engineers and want to understand more on the largest challenges these teams face. Web and backend engineers/managers have described this resource as eye-opening in appreciating the dimensions of good mobile development.

Growing as a Mobile Engineer

Additional eBook for customers of the Full Edition version.

30 pieces of advice for mobile engineers and engineering managers.

  • 65 pages of content

  • Growing to senior and above mobile engineering levels

  • The glass ceiling for mobile engineers

  • Mobile engineering managers: advice to keep growing as a manager

  • Mobile learnings from four years at Uber

Ebook Pricing

The book is currently in beta and is expected to launch Feb 2021. Access the beta at a discount before launch. See team pricing here

The PDF Book

$15Until 31 Mar


Bitrise and Bugsnag
  • 33 mobile engineering challenges
  • PDF Format
  • EPUB & MOBI Formats
  • Growing as a Mobile Engineer ebook

 Scroll to the bottom of the Sponsors section
Get the free PDF book


Coming February 2021.
book cover

Coming Soon

  • 33 Engineering challenges
  • Kindle version also planned
  • Coming February 2021

On Social Media

Frequently Asked Questions

Can I share this book with a group?

While the Building Mobile Apps at Scale PDF can be shared with a group, I encourage each reader to get their own copy.
Growing as Mobile Engineer: if you puchase an individual license, please respect the terms, and do not distribute for others. The book comes DRM-free to make your personal use easy.
Team licenses:

Is there a Kindle or paperback version?

There will be both, following the launch of the book.

I'm not a mobile engineer. Is this book for me?

The book is tailored for software engineers and engineering managers building larger native iOS or Android apps. You might also find this book helpful if you work with teams like this.


About the Author

I've been building native mobile apps since 2010: starting on Windows Phone, later on iOS, and Android. Starting from one person apps, I worked with small teams at Skyscanner, to hundreds of engineers working on the same codebase at Uber.

At Uber, I've been part of the Rider app rewrite, Driver app rewrite, both projects involving hundreds of mobile engineers. The apps my team worked on had 100M monthly users in 60+ countries, with several features built for a single country or region.

I’ve been working on this book - originally meant to be a blog article - on-and-off, for over a year. A Twitter post gave the final push to finish the contents off. The contents were too long for a single post. This is how this book was born.

Follow me on Twitter at @GergelyOrosz, connect on Linkedin or reach me at scale (at) pragmaticengineer (dot) com.