Flutter is Google’s mobile UI framework for crafting high-quality native interfaces on iOS and Android in record time. Flutter works with existing code, is used by developers and organizations around the world, and is free and open source.

fastlane is the tool to release your iOS and Android app.
It handles all tedious tasks, like generating screenshots, dealing with code signing, and releasing your application.

React Native lets you build mobile apps using only JavaScript. It uses the same design as React, letting you compose a rich mobile UI from declarative components.

Ace = JavaScript + Native UI + iOS + Android
for Apache Cordova

Add native power to your shared JavaScript codebase
Works with Ionic, PhoneGap, and all Cordova-based projects