What postgres sync solution should I use to duplicate production, but read it from another application?

I'm a little out of my league with my current problem, but I'm looking for a solution where the following conditions are met:

• My production database reads and writes as it currently does


• My production application ALSO writes everything to a 2nd remote database


• The writes to the 2nd database are frequent and near real time


• I have a separate application that can read from the 2nd database

Both applications are rails, and the main application/database is the product. The 2nd application is a custom built analytics service that only reads from the 2nd database.

Which postgres solution(s) can support these requirements? Thanks.