Regulatory subunit of Kv4/D (Shal)-type voltage-gated rapidly inactivating A-type potassium channels. Modulates channel density, inactivation kinetics and rate of recovery from inactivation in a calcium-dependent and isoform-specific manner. In vitro, modulates KCND2/Kv4.2 and KCND3/Kv4.3 currents. Involved in KCND2 and KCND3 trafficking to the cell surface. May be required for the expression of I(To) currents in the heart (By similarity). Component of heteromultimeric potassium channels. Identified in potassium channel complexes containing KCND1, KCND2, KCND3, KCNIP1, KCNIP2, KCNIP3, KCNIP4, DPP6 and DPP10 (By similarity). The KCND2-KCNIP2 channel complex contains four KCND2 and four KCNIP2 subunits (PubMed:14623880, PubMed:14980201). Interacts with KCND2 (PubMed:10676964, PubMed:14623880, PubMed:14980201). Isoform 1 and isoform 3 interact with KCND3 isoform 1. Probably part of a complex consisting of KCNIP1, KCNIP2 isoform 3 and KCND2. At least isoform 2 and isoform 3 can self-associate to form homodimers and homotetramers. Isoform 3 interacts with KCNIP1 in a calcium-dependent manner. Detected on lipid rafts (By similarity). Expressed in brain. Colocalizes with KCND2 in excitatory neurons including cortical and hippocampal CA1 pyramidal cells. Isoform 3 is expressed in heart and in umbilical vein endothelial cells. Not expressed in fetal heart. Palmitoylated. Palmitoylation enhances association with the plasma membrane. Belongs to the recoverin family.