Volume-Up Tap Automation App

I need a lightweight, native Android utility that listens for the Volume Up key and, the instant it is pressed, fires an automated tap at a user-defined (X, Y) coordinate. The tap must register system-wide—over any foreground app—without requiring root, so the implementation has to rely on Android’s Accessibility framework and nothing more. Key points to hit: speed (latency should feel instantaneous), minimal battery and memory footprint, and clean compatibility across the full Android device landscape. I will be testing on several phones, with special attention to the Samsung Galaxy line, so please keep OEM quirks in mind. A simple configuration screen is enough: enter or pick the coordinate, enable the service, and optionally verify the touch position with a test button. No extra clutter, ads, or analytics. Deliverables • Signed release APK • Full Android Studio project (Kotlin or Java) with clear comments • Brief README covering permission flow, build steps, and any edge-case notes • One-page test log demonstrating the tap firing correctly on at least two Samsung Galaxy models and one non-Samsung device Acceptance criteria • Volume Up press triggers the tap within <100 ms • Tap lands precisely at the saved coordinate every time • Service persists across reboots if the user enables it • No root, no hidden privileges, passes Play Protect scan If this sounds straightforward and you are confident with Accessibility Services, send a short note on how you would minimise latency and handle different screen densities, plus your expected timeline.