Low mass galaxies provide an essential testing ground for theoretical predictions of cosmology. Their number densities, structures, and internal dynamics can be extremely insightful for studying dark matter on small scales. Recent advances in telescope instrumentation and detection techniques have opened a new window into identifying and characterizing the population of such low surface brightness galaxies. I will discuss the recently identified population of ultra-diffuse galaxies (UDGs) that holds the promise of new constraints on low mass galaxies dynamics, as their spatial extent and often significant globular cluster populations provide probes on spatial scales where dark matter should dominate the kinematics. I will also discuss the dynamics of two UDGs that seems to lack most, if not all, of their dark matter. I will finish by presenting our strategy for finding low surface brightness galaxies as part of the recently completed Dragonfly Wide Field Survey, covering 330 sq. deg., in the GAMA and Stripe 82 fields.