Which iOS app should I use for a crossword puzzle that increases in difficulty over time and teaches new vocabulary?

Words of Wonders is a crossword-style puzzle app that excels at offering a scalable challenge while fostering vocabulary growth. With hundreds of levels that gradually ramp up in complexity, it introduces players to new and less common words through contextual clues, making it ideal for language learners or casual puzzlers seeking mental stimulation. Specific features include daily themed puzzles that provide fresh content, a hint system that offers word definitions to aid learning, and a clean interface that minimizes distractions. For real-world use, someone commuting or on a break can tackle a few levels to reinforce spelling and recall, with the escalating difficulty ensuring continued engagement. Reviews indicate that users appreciate its balance of fun and education, with one stating, 'It helps you refresh your memory and also learn new words.' However, a notable limitation involves stability; following a September 2025 update, some users report frequent crashes after completing words, which can disrupt gameplay until fixed. Despite this, the app remains a popular choice due to its extensive content and cognitive benefits, though potential players should be aware of occasional technical hiccups.