InP membranes have appeared in the last decade as a viable integrated photonics platform, suitable for adding photonic functions to silicon electronics. It combines the strengths of silicon photonics (high index contrasts and therefore small footprint devices) with those of generic InP-platforms (monolithic integration of active and passive devices). A range of functionalities has been developed on this platform, which goes by the name of Indium phosphide membrane on silicon (IMOS). Competitive performances have been demonstrated for lasers, fast detectors, waveguides, filters, couplers, modulators, and more. Here, we provide an overview of IMOS and describe recent developments regarding technology and devices. This includes record low propagation losses, plasmonic waveguides, a variety of laser structures, and improved wavelength demuliplexers. These developments demonstrate that IMOS has potential to deliver photonic integrated circuits to a wide variety of application fields, e.g. telecom, datacom, sensing, terahertz, and many others.