Phosphoinositide phosphatase which catalyzes the hydrolysis of phosphatidylinositol 4-phosphate (1,2-diacyl-sn-glycero-3-phospho- (1D-myo-inositol 4-phosphate), PtdIns(4)P). May be functionally linked to OCRL, which converts phosphatidylinositol 4,5-bisphosphate (PtdIns(4,5)P2) to PtdIns, for a sequential dephosphorylation of (PtdIns(4,5)P2) at the 5 and 4 position of inositol, thus playing an important role in the endocytic recycling (PubMed:25869668, PubMed:25869669). Regulator of TF:TFRC and integrins recycling pathway, is also involved in cell migration mechanisms (PubMed:25869669). Modulates AKT/GSK3B pathway by decreasing AKT and GSK3B phosphorylation (PubMed:17322895). Negatively regulates STAT3 signaling pathway through inhibition of STAT3 phosphorylation and translocation to the nucleus (PubMed:25476455). Functionally important modulator of cardiac myocyte size and of the cardiac response to stress (By similarity). May play a role as negative regulator of axon regeneration after central nervous system injuries (By similarity). May be involved in insulin granule docking at the plasma membrane of pancreatic cells, an essential step for insulin secretion (PubMed:31533953). {ECO:0000250|UniProtKB:Q8CDA1, ECO:0000269|PubMed:17322895, ECO:0000269|PubMed:25476455, ECO:0000269|PubMed:25869668, ECO:0000269|PubMed:25869669, ECO:0000269|PubMed:31533953}. This is the function of INPP5F (inositol polyphosphate-5-phosphatase F, Ensembl gene identifier ENSG00000198825).