Why did Push notifications work in development but not in production (iOS)?
This is a common question. Apple uses basically two servers for their APNS protocol: one is their sandbox (for testing purposes) and the other is for production (live). When an App is defined as Development - Connecting to testing servers in our Application the APNS Sandbox is invoked.
When the App goes into production, it is recommended to create another App on our Console (which will have different app keys and such) in order to "start clean" and also in order to follow the release standards.
Here is an image showing the differentiation between Production and Development in certificates:
Thus always remember to use the adequate status in the MOCA console, even if you use an universal certificate.
More about APNS can be found at Apple's APNS Overview. A good guide on what could of gone wrong can be found at Apple's official troubleshooting Push Notifications documentation.