Converts adenosine 3'-phosphate 5'-phosphosulfate (PAPS) to adenosine 5'-phosphosulfate (APS) and 3'(2')-phosphoadenosine 5'- phosphate (PAP) to AMP. Is also able to hydrolyze inositol 1,4-bisphosphate. adenosine 3',5'-bisphosphate + H2O = AMP + phosphate 1D-myo-inositol 1,4-bisphosphate + H2O = 1D-myo-inositol 4-phosphate + phosphate Signal transduction; phosphatidylinositol signaling pathway. A number of isoforms are produced. According to EST sequences. Belongs to the inositol monophosphatase superfamily.