Based on the users' reviews of the "Sixteen - 3D Assemble Puzzle" app, here are three cons and pros in English, within the 15-word limit for each item: **Cons:** 1. Some users found the puzzles too easy, lacking challenge and engagement. 2. Others experienced frequent errors and crashes, disrupting gameplay. 3. A few reviewers felt the app's visual quality and graphics were disappointing. **Pros:** 1. Users praised the app's unique 3D assembly puzzle concept as engaging and fun. 2. Many reviewers appreciated the varied puzzle levels, with increasing difficulty. 3. Others enjoyed the relaxing and calming atmosphere the app provided. Please note that these conclusions are based on a general analysis of the reviews and may not be representative of every user's experience with the app.