According to the React Native Express site posted on HN a bit ago, there are 3 worth noting. Would you recommend any of these? What about one not listed here?
Ignite - https://github.com/infinitered/ignite
Pepperoni App Kit - https://github.com/futurice/pepperoni-app-kit
Snowflake - https://github.com/bartonhammond/snowflake
Source: http://www.reactnativeexpress.com/boilerplates