Amorphous oxide semiconductor thin film transistors and sensors constitute fundamental building blocks for a new generation of applications ranging from interactive displays and imaging to future electronic systems that are unconstrained by form factor. This makes the quest for high mobility materials processed at low temperatures even more compelling, to enable the layering of circuits and systems on plastic and possibly even paper substrates. Transparency is also an attractive feature that enables seamless embedding of electronics for the immersive ambient. This paper reviews the current status of the ubiquitous oxide semiconductor technology for flexible and transparent interactive displays, along with demonstrated examples of continuous thin film and nanowire systems for the transistor and sensor. Issues related to photosensing and active matrix operation are discussed along with solutions addressing the problem of threshold voltage instability and its compensation for fast recovery, particularly after light stress. Physics-based compact models for expedient design and simulation of analog and digital circuits are reviewed along with examples of key system building blocks. Finally we attempt to conceptualize a thin film transistor (TFT)-based fully heterogeneously integrated and autonomous system that can be realized using a combination of oxide and other technological routes.