In this review article, the recent experimental and theoretical research progress in Bi2Se3-and Bi2Te3-based topolog-ical insulators is presented, with a focus on the transport properties and modulation of the transport properties by doping with nonmagnetic and magnetic elements. The electrical transport properties are discussed for a few different types of topo-logical insulator heterostructures, such as heterostructures formed by Bi2Se3-and Bi2Te3-based binary/teary/quateary compounds and superconductors, nonmagnetic and magnetic metals, or semiconductors.