Trailmark

Trailmark is a native iOS app I built for anyone chasing the goal of visiting every US National Park. It ships with the complete field guide to all 63 parks — real photos, geography, activities, best times to visit, and quiet local details — so the whole thing works even when you have no signal on a switchback in the Sierras. Open the app on the road and Discover surfaces the closest parks to you by distance, sorted so a spontaneous detour is one tap away. Every park has its own detail page with a curated hero image, a map pin, and everything you need to plan the visit or just remember why you went.

The app is designed around a passport metaphor. Every time you mark a park visited, you earn a stamp; strings of visits unlock milestone badges — your first park, five parks, a full region, all 63. A private, on-device journal lets you log dates, notes, and photos for each trip, so the app slowly becomes a record of your own trail rather than a static checklist. The Stats view tracks progress by region and time, the visual language leans into deep forest greens and warm gold in a field-guide serif, and everything lives locally — no accounts, no servers, no analytics. Trailmark is meant to feel like the paper passport you buy at a visitor center, only smarter.