This spring, I've been shooting and converting much of my iPhone 6+ photographs with MPro a dedicated BW iPhone app, and Filmborn, which is developed by Mastin Labs here in Seattle, Wash. Kirk Mastin is the Founder and Ceo; he's a lover of photography and film, and you can feel and see his passion. Head over to its webpage or read though the Apple App Store reviews to get a sense of what the Filmborn app can do. I love the customization and its fidelity to film emulation via choices with Fuji, Ilford and Kodak. You won't find blown out highlights, crazy grunge effects, or highly stylized tones/colors/hues--just clean, beautiful simulaiton of film. What's here is the look and feel of film that works. I'm a stickler for a particular black and white look, which is contrasty and inky. I love the Fuji bw choices. Check both these apps out and let me know what you think. Here's another sample on my flickr stream.
Photo credit: Star Rush with iPhone 6+ and Filmborn in Astoria, Oregon, in 2017