Based on the user reviews, here are three cons and three pros of the "Double Up 3D" app: **Cons:** 1. Poor online multiplayer connection, often disconnects during gameplay. 2. Lacks depth in level design, making it too easy and repetitive. 3. Difficulty in zooming and rotating 3D objects, causing frustration. **Pros:** 1. Engaging and intuitive 3D model creation process, easy to learn. 2. Great educational value, helps users understand 3D modeling concepts. 3. Regular updates with new features and content, keeping users engaged.