What is it and why do it?
Establishing a a code review policy and process is a best practice to help ensure a quality system. A code review is a process by which developers have their source code reviewed by another developer in order to discover bugs, scrutinize coding conventions, and look for potential bottlenecks and resource leakage. The intent of a code review is to catch bugs/issues/defects before the offending code is deployed to a production environment and to transfer knowledge of implementation details to the rest of the team. In addition, code reviews may be used to ensure code is well documented and meets any coding conventions that have been established. For an example of what to look for see this code review check list.
Examples and References
In this example, the team uses Git Hub tickets to help manage the code review process. https://wiki.openmrs.org/plugins/servlet/mobile#content/view/2818253