What did we have at the start?

• Fully implemented web-app (frontend + backend + db)
• Dev team of 2 people
• Some designs. Kind of.

What restrictions did we have?

• Minimize 'learning technology' time
• Minimize development time
• Reduce the cost of further app support
• Minimize feature delivering time

Choosing a right tool

• Native app
• Web View mobile app
• Compiled mobile app
• React Native

What's wrong with native apps

• 1 app per 1 platform
• No code sharing
• No experience sharing between teams
• No hot reloading

Web technologies

Hybrid mobile apps

Web View apps

Why not Web View?

• They are slow (really slow)
• No complex gestures
• Cannot use native components
• No platform specific look and feel
• Incomplete API support

Hybrid mobile apps

Compiled mobile apps

Why not compiled apps?

• Don't really support everything
• Hard to debug
• Need to understand platform specific architecture
• Lack of open source libraries
• Delayed support for the latest platform updates

React consists of

React consists of

React consists of

Write once

Get platform specific UI

Platform Specific Code

• Using Platform module
  1. Platform.OS method
  2. Platform.select method
• Using platform-specific file extensions

Platform.OS method

Platform.select method

Platform-specific file extensions

• .android.js
• .ios.js
• .windows.js (custom one)

How React Native works

Performance

Performance

Performance

Performance

Performance

Set state from JS on every touch event

Implement the Swipeable container handling touch events in native

Using a native driver

How to use it

Ready to go

				npm install react-native-cli
				react-native init ExampleApp
				cd ExampleApp
				react-native run-android
			

NOTE: You should also install Android SDK and Xcode

What do we have out of the box?

• Babel
• Hot reloading
• Dev Tools. Sort of.
• Debugging tool

Dev tools

Dev tools - Inspector

Dev tools - Perf Monitor

Conclusion

Cons

• It's still young
• Ecosystem isn't big
• You still have to be familiar with key concepts of native app development
• Bridge performance is low
• Hard to implement some trivial for Web things

Did it fit our goals?

Yes

Would we choose it again if we have to start a new project now?

Yes

Should you use it?

You decide

But remember

React Native doesn’t mean end on Native. You’re still doing it, but doing less of it and concentrating your efforts on the important parts