I've been buying 7artisans lenses for a while now. They are the best bang for buck ratio as they are very affordable, are great for low-light, and feel very premium.

Note that this is a manual focus lens. I changed from auto focus to manual focus for my vlogs as I noticed sometimes the camera would focus my background instead of me.. With manual focus I just have to be careful not to move the camera too far or too close while walking.