Who is? Brain Teaser & Riddles represents Unico Studio's latest entry into the crowded puzzle game market, building upon their successful Brain Test franchise. This Android-exclusive title shifts focus toward social deduction puzzles where players analyze scenarios, examine character statements, and identify inconsistencies to solve mysteries. The game presents itself as a completely free experience supported by advertisements, positioning itself as an accessible option for casual puzzle enthusiasts. The core gameplay revolves around three primary puzzle types: 'Who is Lying?', 'Who is the Killer?', and 'Who is the Imposter?' scenarios. Each level presents characters with conflicting statements, visual clues, and contextual details that require careful observation and logical deduction. The game employs a tap-to-interact mechanic where players examine dialogue bubbles, character expressions, and environmental elements to uncover contradictions. Solutions often require lateral thinking rather than straightforward logic, aligning with Unico Studio's signature 'tricky puzzle' design philosophy. User experience is characterized by a minimalist interface with cartoonish character designs and intuitive touch controls. The game employs a linear progression system where solving one puzzle unlocks the next, creating a binge-play friendly structure. Real-world usage patterns show peak engagement during short breaks, commute times, and as a stress-relief activity, with average session times ranging from 5-15 minutes. The ad-supported model presents video advertisements between levels, though user feedback suggests their frequency is manageable compared to similar free puzzle games. User reviews consistently highlight the game's stress-relieving qualities and engaging puzzle design. Barrillah Nassali2580 (June 2, 2025) notes the game 'relieves my stress' while criticizing the limited level count, having completed the game within a day. Andi Trickett (April 12, 2025) initially expressed concern about advertisement frequency but upgraded their rating after finding ads 'nowhere near as bad as thought.' Serena Davis (June 20, 2025) describes it as 'really amusing and good for killing time,' representing typical positive feedback about the game's entertainment value. The game's primary strength lies in its clever puzzle design and completely free accessibility, though it suffers from limited content volume and reliance on advertisement revenue. The deduction-based mechanics provide genuine cognitive engagement, but the experience is shortened by relatively few levels. Ideal for puzzle enthusiasts seeking quick mental stimulation without financial commitment, though players preferring extended gameplay may find the content insufficient. The advertisement implementation strikes a reasonable balance between monetization and user experience compared to industry standards.