Kotlin Multiplatform Pros and Cons for App Development

This probably isn’t the first article you’ve read about cross-platform mobile app development. It might not even be your first article trying to look at pros and cons of using Kotlin Multiplatform for app development. If you’re like us, you recognize that there must be a way to share code between iOS and Android while respecting the unique environment and user experience of each.

Our Trial Project

At FreshWorks Studio, we recently created “The Deals App” for the BC Federation of Students, and we did it using Kotlin/Multiplatform (KMP) for iOS and Android. At the time of writing, we’ve been maintaining the app for roughly 1 year, and we’ve experienced a lot of the pros and cons to using this new, experimental technology by JetBrains. We adopted KMP for the Deals app since we believe in sharing business logic, and in how it solves the disadvantages of other cross-platform solutions. We wanted to be an early adopter of a technology that we anticipate will revolutionize mobile app development.

Before starting development on The Deals App, we had been researching Kotlin Multiplatform pros and cons while studying their documentation. We believed in the KMP approach: to share logic without mandating an entire architecture. We hoped that sharing logical components between mobile apps would reduce the development time, improve the quality of the code, and have no impact on performance.

In the past, we’ve examined the cost and benefit of native vs hybrid applications. We had investigated several other cross-platform technologies, like React/Native and Flutter, but we didn’t like how those technologies made the UI identical for both platforms, and we were intimidated by the all-in commitment they required. Our Android and iOS teams agreed that for performance’s sake, the UI should be native to the OS.

When The Deals App came along, it looked like the perfect fit for Kotlin Multiplatform. It had a shorter development schedule (we didn’t want to get locked-in on a huge app), and it had few OS-dependent features like BLE and push notifications, which, although possible to develop with KM, yield diminished benefits. Our developers are also cross-functional and have an understanding of how the other platform works. This helped a lot in coming up with an architecture for the app.

How It Helped Us

Complications to Consider

Relative to the more familiar native iOS or Android which we have used for dozens of apps in the last few years, Kotlin Multiplatform presented us with a unique set of hurdles to overcome. Here are a few worth mentioning.

Longer Project Setup

Since it was our first trial, the project initialization took us longer than expected. We had to do a lot of brainstorming to settle on approaches for the application architecture, Git repository management, Jira tickets, CI/CD, etc. We came up with several approaches before finally finding the one that worked well for us.

Our development team loved working with Kotlin/Multiplatform for The Deals App and would highly recommend it for developing cross-platform solutions. However it is important to understand that it’s not a “one size fits all” situation with mobile development.

A lot of factors affect the decision on which method to use for developing mobile apps. It’s important to consider the complexity of the application, and its reliance on OS-dependent features. In many cases, it may be better to develop natively. For this project, our expertise with mobile development and understanding of the nuances of Kotlin Multiplatform helped us to write robust, well-tested code.

0 Crashes To Date

According this Crittercism Report (which is in line with my own experience) 47% of mobile apps crash more than 1% of the time.

For the Deals apps, we have been very happy with the results. Our apps have been live on the Google Play Store and Apple’s App Store since September 2019, with thousands of users and no reported crashes yet.