As a unique group of advanced polymer-based materials, conductive polymer nanocomposites combining the flexibility and/or conductivity of the polymer with the distinct properties of nanofillers have found many intriguing applications in various modern devices. This review provides a concise yet inclusive introduction to the concept of conductive polymer nanocomposites backed by some modern technologically advanced devices resulting from the advances made in this area. The most commonly adopted preparation strategies are first summarized, which mainly include direct mixing/blending (ex situ) and in situ methods (in situ polymerization or nanostructure synthesis). Selective examples of device applications are then detailed including organic light emission diodes (OLEDs), photovoltaics (PV), electrochromic devices (ECDs) and others. Lastly, concluding remarks and future perspectives are given for conductive polymer nanocomposites as viable electronic integration tools.