The increasingly popular use of the Internet and social media sites has brought about, threatened to bring about, or made distinctly worse a myriad of epistemically problematic phenomena. My dissertation consists of three essays, which each focus on a different epistemic issue or threat that we find ourselves faced with in this new digital age. The first essay centers on the epistemic dangers posed by the tendency for ideological (self-)segregation, which is something that has become more of a cause for concern than ever due to the widespread availability of the Internet. I elucidate the ways in which this tendency plausibly interacts with our propensity for motivated reasoning, and argue that their interaction threatens to produce unique epistemic problems. I furthermore argue that adequately remediating such problems would require interventions that are unlike those that have been proposed for remediating the epistemic problems caused by phenomena more familiarly associated with ideological segregation – viz., echo chambers and epistemic bubbles. In the second essay, I argue in support of two theses relevant to the alarming proliferation of fake news and political misinformation on social media. The first says that the incentive structure generally found on social media sites encourages ordinary political partisans especially to perform what essentially amount to unreliable acts of testimony concerning political matters; the second says that, granted the truth of the first, ordinary consumers of social media typically ought to try to avoid and reduce their exposure to the social media-mediated political testimony (i.e., the politically relevant posts and reposts) of their politically partisan peers. In the third and final essay, I argue that certain kinds of microtargeted political influence campaigns – made newly feasible thanks in large part to the increasing popularity of the Internet and social media – are distinctively epistemically problematic. To establish this, I draw out how such campaigns plausibly threaten to encourage in the individuals that they target the development of various epistemic vices and the atrophying of certain epistemic capacities, and also plausibly cause democracy (qua group political decision-making process) to produce epistemically worse outputs.