What are some alternatives?
When comparing ReactNativeAutoUpdater and Marvel for Sketch, you can also consider the following products
React Navigation - Description will go into a meta tag in <head />
Fluid for Sketch - Sketch plugin to make your responsive designs more efficient
Native Navigation - Application and Data, Mobile, and Cross-Platform Mobile Tools
Anima - Create High-Fidelity Prototypes in Sketch
CodePush - CodePush is a cloud service that enables Cordova and React Native developers to deploy mobile app updates directly to their users' devices.
Webflow Flexbox UI Builder - Build flexible, responsive layouts — without writing code