MTG Familiar is a mature, open-source Android companion app for Magic: The Gathering. It provides a comprehensive suite of offline-capable tools including card search with advanced filtering, life counter with commander damage and poison tracking, mana pool, dice roller, trade and wishlist management, round timer, comprehensive rules browser, judge documents (MTR, IPG, JAR), deck builder with import/export and statistics, and the MoJhoSto random card generator. The app is built as a single-module Android project using AndroidX, with a local SQLite database for card data (updated via JSON patches from a GitHub repository), TCGPlayer API integration for market prices, and Glide for card image loading. The architecture follows standard Android patterns: a main Activity (FamiliarActivity) manages a navigation drawer and fragment transactions, with each tool implemented as a Fragment. Data access is centralized through CardDbAdapter and DatabaseManager, with custom Views for mana symbols, color pie, and token-based input. The codebase is well-organized but shows signs of age with deprecated API usage (AsyncTask, PreferenceFragment) and some large, tightly-coupled fragments. It is actively maintained (last commit 2026-06-04) with regular database updates and community contributions.