I need a lightweight utility application built exclusively for HarmonyOS. The scope is intentionally tight—just five screens—but those screens must feel polished, fast, and fully native to Huawei’s ArkUI framework. Core requirements • Real-time notifications: use the HarmonyOS notification service so alerts arrive instantly, even in the background. • Integration with other apps: the tool has to pull or push data to at least one external HarmonyOS-compatible app or system module Deliverables 1. Complete ArkUI source code organised and documented. 2. Release-ready HAP package that installs cleanly on current HarmonyOS phones and tablets. 3. Brief README explaining build steps plus any required Huawei kits or permissions. 4. One revision cycle after initial hand-off for minor tweaks across the five screens. Acceptance criteria: the app launches without errors on HarmonyOS 3+, all five screens are reachable through intuitive navigation, notifications fire in real time, and at least one external app interaction is demonstrated in a test scenario. That’s the entire job; concise yet demanding attention to native details. I’m ready to move quickly once you confirm timeline and approach.