Help me kick off a new app concept called ‘Urban Explorer’, an offline‑first city discovery tool for people who like to wander and pin interesting spots. Users should be able to download a city map for offline use, drop personal pins with notes and photos, and browse everything in a clean, readable Light Mode interface built with Jetpack Compose. On foldable devices, the unfolded view should become a two‑pane dashboard: the map on one side and a list of saved pins or search results on the other.

Technically, start this as a Kotlin project using an MVI approach to keep map and location state predictable. The app must run on devices with or without Google Play Services: use a map SDK that doesn’t depend on GMS (for example, Mapbox or osmdroid), and make location work with a graceful fallback—prefer Google’s FusedLocationProvider when available, otherwise use Huawei Location Kit or the platform’s GPS provider. All pins and offline map data should be stored locally with Room and the device file system.