This paper is devoted to the design and implementation of a multipurpose platform (MPP) for power system monitoring and analysis. This MPP is a novel device, which combines the abilities of a power quality (PQ) analyzer, an event logger, a synchronized phasor measurement unit, and an interarea oscillation identifier, all in one device. The multiple functions of the proposed MPP can serve the needs of the power system operators (SOs) as a wide-area monitoring system to observe the states and stability of the power system, and as a PQ analyzer to monitor the PQ events and parameters, permanently. Furthermore, the algorithms of flicker and harmonic current contributions at a point of common coupling can be embedded on this MPP, to determine the individual contributions of different loads supplied from the same bus. The operational features of the developed MPP have been tested on the Turkish electricity transmission system and its interfaces with the distribution system by installing 450 MPPs and integrating them with a monitoring and control center. The proposed all-in-one MPP can therefore meet the multiple requirements of the power SOs to serve the needs of modern electricity markets and convert an ordinary electricity system to a smart grid.