Receptor tyrosine kinase which binds promiscuously membrane- bound ephrin family ligands residing on adjacent cells, leading to contact-dependent bidirectional signaling into neighboring cells. The signaling pathway downstream of the receptor is referred to as forward signaling while the signaling pathway downstream of the ephrin ligand is referred to as reverse signaling (PubMed:11870224, PubMed:12794130). Highly promiscuous for ephrin-A ligands it binds preferentially EFNA5 (By similarity). Upon activation by EFNA5 regulates cell-cell adhesion, cytoskeletal organization and cell migration (PubMed:11870224). Also activated by EFNA1, inhibiting epithelial-to-mesenchymal transition of cardiac cells and playing a role in heart development (PubMed:12794130). Involved in the retinotectal mapping of neurons. May also control the segregation but not the guidance of motor and sensory axons during neuromuscular circuit development (By similarity). {ECO:0000250|UniProtKB:P29319, ECO:0000269|PubMed:11870224, ECO:0000269|PubMed:12794130}. This is the function of Ensembl gene identifier ENSG00000044524 (EPHA3, EPH receptor A3).