An XDA author used Claude Code with Opus 5.5 to build a family Android grocery app. Kotlin and Jetpack Compose provide the interface, while Firebase Google sign-in and Firestore synchronize quantities, notes, and purchase status, including changes made offline. Each person schedules reminders locally rather than notifying the whole family, avoiding a separate push server. The project uses Firebase’s free Spark plan and a private GitHub repository, with access restricted to family accounts; the author exhausted the five-hour usage allowance twice while building it. This small personal case does not demonstrate unlimited free operation or automatically verified security.