This chapter discusses the development of polymer modified quartz tuning forks (QTFs) as a niche chemical sensor. The chapter begins with a short introduction to chemical sensors and how they have become imperative to our quality of life. It then moves on to describe the development of QTFs as chemical sensors from their original use as commercial timing crystals. The chapter also discusses the various ways in which QTFs may be used as sensors and focuses specifically on the development of polymer modified QTFs as direct chemical sensors. The unique ability of these polymer modified QTF sensors to detect analytes by measuring variation in Young's modulus of polymer is detailed by exploring the various applications and use cases which have been reported in literature. The chapter aims to offer a glimpse of the potential of QTF direct sensors by showcasing the diversity, sensitivity and selectivity of QTF sensors towards different analytes for various applications.