Due to the continuous growth of E-Commerce platforms, more and more data is becoming widely available. Almost every online transaction, from buying products on Amazon to renting vacation homes on Airbnb, allows for users to leave feedback in the form of customer reviews. Therefore, there is a need to provide an overview of the status of customer review analysis. This paper systematically reviews research works conducted in the past ten years (2010–2020) to identify how customer reviews are being analyzed and how this analysis can serve the consumers or vendors. We present several commonly used machine learning algorithms, datasets, and numerous applications of customer review analysis to provide insight as well as discuss directions for future research.