Stelline is a calm star battle-style logic game designed for those who enjoy solving puzzles through reasoning rather than trial and error. It offers a unique experience where every board is generated directly on your phone, ensuring an engaging gameplay. Each board is guaranteed to have exactly one solution, validated by a powerful deduction engine that also provides hints. With no ads and no account needed, everything stays on your device, giving you a completely private puzzle-solving experience.

In Stelline, the main rule is to place one queen in every row, every column, and every coloured region, making sure that no two queens touch—even at the corners. Once you get the hang of that, you can switch to the 2-star mode, where you place two stars in every row, column, and region on boards up to 11×11. This mode maintains the same challenge: the stars must never touch.

One standout feature of Stelline is that you have unlimited puzzle boards. Since these boards are generated on your device, there’s no limit on how many puzzles you can solve, and you don’t need to download any additional packs. Each board is carefully checked by an exact solver to guarantee that it provides only one solution, always. You can enjoy 1-queen boards that range from 6×6 to 11×11, or take on the challenge of 2-star boards from 9×9 to 11×11. Plus, every day brings a new board that is the same for all users on both Android and iPhone, with an archive of past boards for you to revisit.

To support your puzzle-solving journey, Stelline uses a deduction engine that employs 13 logical deduction techniques. The game grades difficulty through these techniques, so you can tackle easy, medium, and hard boards that require direct deductions only. If you’re feeling brave, you can attempt the expert puzzle mode, which needs what-if reasoning and poses an extra challenge.

The hints in Stelline are designed to teach you. Each hint starts by showing a counter for misplaced queens and misplaced dots, helping you assess your reasoning. If you’re unsure, the "Show me where" feature guides you through one logical step at a time, highlighting the row, column, or region involved in the next deduction. This way, you can learn as you play. Hints are unlimited, so if you manage to solve a board without using any, you'll earn the Flawless badge.

Controlling the game is straightforward, with clean solving controls for optimal enjoyment. You can tap a cell to cycle through its options—empty, dot, queen, or star. If you prefer a hands-on approach, you can drag across cells to dot them or erase them by starting on a dot you’ve placed. When a queen or star is placed, it automatically dots its eight neighbouring cells. The game also includes an auto-check mechanic that identifies any queens or stars that touch or exceed their assigned row, column, or region.

Customization options enhance your gameplay experience in Stelline. You can choose between an original pastel palette with unique region colours or a classic black-and-white look for those who prefer a traditional feel. There's even a high-contrast colour mode for colour-blind accessibility, complete with distinct fill patterns for each region. Furthermore, the app supports both light and dark themes, letting you pick whatever suits your style.

Stelline is also designed to accommodate everyone, with seven language options including English, Deutsch, Español, Français, Italiano, 日本語, and Português (Brasil). TalkBack support allows users to hear announcements about the state of each cell, making it accessible for visually impaired players. The app respects larger font sizes and offers a setting to remove animations.

Your privacy is a top priority with Stelline. The app demands no internet access, meaning your boards, settings, and progress are safely stored on your phone, ensuring a truly offline puzzle-solving experience. This is perfect for playing on a plane or underground.

Made by a one-person development studio, Stelline (which means little stars) reflects a dedication to fair, well-crafted puzzles. The generator, solver, and deduction engine have all been written from scratch, providing a consistent experience on both Android and iPhone. Each board's design aims to challenge your reasoning skills while keeping the experience enjoyable.

In summary, Stelline offers a rich puzzle-solving experience with its star battle-style style, logical reasoning puzzles, and an easy-to-use interface. It’s an excellent choice for fans of logic games looking for a wholesome way to unwind through challenging and engaging gameplay.