I4, i4, I 4 or I-4 may refer to: Arts, entertainment, and media I-4: Loafing and Camouflage, a Greek film Military 1st Life Grenadier Regiment (Sweden) (1816–1927), a Swedish infantry regiment , a World War II Type J1 submarine of the Imperial Japanese Navy Life Grenadier Regiment (Sweden) (1928–1997), a Swedish infantry regiment Tupolev I-4, a 1927 Soviet aircraft Science and technology I-4 satellite i4, an integer in XML-RPC Transportation I4 engine, a piston engine Interstate 4, an interstate highway in Florida BMW i4, a German mid-size electric sedan Interstate Airlines, by IATA airline designator LB&SCR I4 class, a British locomotive See also iPhone 4, a smartphone