Devices for delivering pharmaceutical formulations into the eye are described. The devices may be integrated to include features that allow safe and atraumatic manipulation of the devices with one hand. For example, accurate placement, including proper angulation, of the device on the eye and injection of a pharmaceutical formulation into the eye can be performed using one hand. The devices may also include improved safety features. For example, the devices may include an actuation mechanism that controls the rate and depth of injection into the eye. Some devices include a dynamic resistance component capable of adjusting the amount of pressure applied to the eye surface. Related methods and systems comprising the devices are also described.