PRP stands for Partner Reporting Portal.
PRP is an open-source project and can be found on Github.
PRP consists of two somewhat distinct user experiences targeting different but potentially overlapping use-cases. This is what is referred to as IP and Cluster Reporting. More details if you click on each of them in the left hand navigation.
Both of these sub-systems is built on top of the same data model and all the data is stored in the same database.
The UX / visual design philosophy builds on Google Material Design, with variations.
The technical design philosophy for PRP builds on what has already been established by the eTools team at UNICEF. More information here: https://github.com/unicef/etools