This document discusses cross-platform mobile development and compares tools like Xamarin, React Native, and Ionic. It notes that native mobile development requires separate codebases for each platform while cross-platform tools allow code reuse. Xamarin offers the fullest integration with native platforms but at a higher cost, while React Native and Ionic use JavaScript. Performance varies by tool, with Xamarin using native components and React Native using custom rendering. Development experience also differs, with automatic reloading and hot swapping available in some tools. The best choice depends on project needs and developer skills.

1. Cross platform development
Should I use it? What should I use? When should I use what?
Mikael Stalvik - Evolve Technology

2. Mikael Stalvik
Evolve Technology

3. Native applications
● iOS: Swift or Objective-C
● Android: Kotlin or Java
● UWP: C#
● Pros
○ As native as it gets, latest updates
○ Best performance, smallest size
● Cons
○ Code redundancy per platform
○ Possible multiple deployment environments

4. Cross platform development
● Multiple tools exists; Xamarin, React Native, Ionic
● Reuse code, tests and logic between platforms
● When it can/should be considered?

5. Overview
● Xamarin: .NET based framework. Two ways, Native vs. Forms
● React Native: JavaScript based (React)
● Ionic: JavaScript/HTML based (Angular with TypeScript)

6. Performance comparison
● JIT and AOT compilation
● 64-bit requirement
● Xamarin: AOT for iOS, JIT for Android (can be AOT). 64-bit is no issue.
Rendering used native components and pipeline.
● React: Interpreted, 64-bit issues on Android. Fast custom DOM for
rendering, not cascading stylesheets (by default) for speed
● Ionic: WKWebView used by default. UIWebView can be used. 64-bit
support for iOS, unclear for Android. Rendering via HTML and CSS

7. Performance comparison
Xamarin React Ionic
Running code iOS AOT Interpreter Interpreter
JIT via plugin
Android JIT/AOT JIT JIT
64-bit iOS Yes Yes Yes
Android Yes No ?
GUI iOS/Android Native “Native”,
rendered
HTML

8. Development convenience
● Reloading scenarios
● Instant updates (React, Ionic)

9. Development convenience
Official tools Xamarin React Ionic
Manual
restarting
Yes Yes Yes Yes
Automatic
restarting
No No Live/hot rel. Yes
Hot swap iOS No No Hot rel. No
Android Instant run No Hot rel. No
Cold swap iOS No No Live rel. Yes
Android Instant run Fast depl. Live rel. Yes
Browser dev. No No Partially Looks different
Instant updates iOS No No Yes Yes

10. OS integration and existing code
● Standard libraries
● Consuming libraries
● Native integration (Xamarin, React)
● GUI
● Background execution

11. OS integration and existing code
Xamarin React Ionic
Code binding Use Java, objc and
@objc Swift
Any binary lib. Adaptor required Adaptor required
Use cross-platform
code in native app
Partially Yes No
Standard lib. binding Supported feature
set
Full Partial Partial
Binding type 1-1 Abstraction layer Abstraction layer
GUI All widgets Yes No No
Native look & feel Yes Partial Partial
Background exec. iOS Yes No support Very limited
Android Yes Headless JS Limited

12. Conclusion
● Xamarin is the fullest cross platform framework...
● ...comes with a cost
● Choose framework depending on project, cost and competence

13. Appendix - Xamarin
Code distribution Xamarin Native vs. Xamarin Forms
Xamarin Native Xamarin Forms
UI (per platform) UI (per platform)
Forms (abstraction)
View models and models View models and models

14. Questions & contact
● Questions?
● mikael.stalvik@evolvetechnology.se