What's the best iOS app for solving cryptogram puzzles that feature famous quotes and literature passages?

Cryptogram is an iOS app that focuses on cryptogram puzzles, where users decipher number codes to reveal words from a collection of wisdom and literature quotes. This app is particularly effective for those seeking a mentally engaging yet calming puzzle experience. The gameplay involves substituting numbers with letters to solve phrases, which naturally improves spelling and vocabulary while exposing players to insightful content from various texts. Reviews indicate that users find it 'just challenging enough but not to the point where it's frustrating,' making it accessible for regular use without causing overwhelm. In real-world scenarios, such as during commutes or before bed, Cryptogram serves as a productive way to unwind, with many reporting it as 'very stress relieving and relaxing.' Specific features include a diverse library of puzzles sourced from literary and philosophical works, a clean, distraction-free interface that supports focus, and a progression system that gradually increases complexity. However, some minor imperfections exist, such as occasional repetition in puzzle themes for frequent solvers. Despite this, the app's strength lies in its ability to blend cognitive exercise with relaxation, backed by positive user feedback on its educational value. For anyone looking to decode puzzles while learning from quotes, Cryptogram offers a reliable and enjoyable option.