Cortex is a calm brain-training app built around a single idea: sharpen your mind without surrendering your privacy. Seventeen games and puzzles sit in one place, eleven brain-training games across memory, focus, reading, timing and spatial skills, three skill drills, and three classic puzzles: Sudoku, Word Search and Nonogram.
Its standout feature is Peak Hours: a quick reaction check you can take any time of day. Over time it charts when your mind is sharpest and names your type, morning lark, night owl, or steady all day. No other brain trainer has it. The skill drills are practical too: Mental Math teaches a real calculation trick then drills it, Track is the multiple-object task used in sports-vision training, and Remember-To trains everyday memory. A built-in Speed Reader turns any TXT, PDF, DOCX or EPUB into an RSVP reading session, processed entirely on your device.
Privacy here isn't a setting you switch on, it's how the app is built. No account, no analytics, no third-party trackers; your stats never leave your phone, and everything works offline. A single one-time purchase unlocks everything, with no recurring charges ever, sample several games free, then unlock the rest for good. Available on Android, with iOS coming soon to the App Store. English and Dutch, light or dark, with your own accent colour.