Regulator of the Hippo/SWH (Sav/Wts/Hpo) signaling pathway, a signaling pathway that plays a pivotal role in organ size control and tumor suppression by restricting proliferation and promoting apoptosis. The core of this pathway is composed of a kinase cascade wherein Hippo (Hpo), in complex with its regulatory protein Salvador (Sav), phosphorylates and activates Warts (Wts) in complex with its regulatory protein Mats, which in turn phosphorylates and inactivates the Yorkie (Yki) oncoprotein. Kibra acts synergistically along with Ex and Mer to regulate the Hippo signaling pathway (By similarity). Forms a complex with Mer and Ex. Interacts (via domain WW 1) with Ex (via RXPPXY motif). Interacts with Mer, Sav, Hpo and Wts (By similarity). Localizes at the apical cortex of epithelial cells and cytoplasmic, punctate. Belongs to the WWC family. KIBRA subfamily.