Acts as a regulator of endocytic traffic by participating in membrane delivery. Required for the abcission step in cytokinesis, possibly by acting as an 'address tag' delivering recycling endosome membranes to the cleavage furrow during late cytokinesis (By similarity). May play a role in differentiation during retinal development, in a Rab11-independent manner. Homodimer. Forms a complex with Rab11 (RAB11A or RAB11B) and ARF6. Interacts with RAB11A; the interaction is direct. Forms a heterooligomeric complex with RAB11FIP2, RAB11FIP3 and RAB11FIP5 (By similarity). Interacts with ECPAS (By similarity). Recruited to the cleavage furrow and the midbody during cytokinesis. Strongly expressed in the developing retina. Expressed predominantly in neural tissues. The RBD-FIP domain mediates the interaction with Rab11 (RAB11A or RAB11B).