Although Helms uses two add-ons, he himself explains that it is not the usual footage “technically shot with the iPhone but with a full crew and tens of thousands of dollars of lights and film kits.”
Instead, as the director reveals in a video tutorial, he mostly only used a gimbal and a relatively low-cost variable neutral density filter.
Of course, Helms is a professional videographer and editor and admits that while the shoot was lacking in accessories, it took a long time. The director stated that his final editing typically uses 1% to 5% of the material shot, with a lot of time dedicated to the editing phase.