Based on the users' reviews, here are three pros and three cons of the Gun Builder 2 app: **Pros:** 1. Users praise the app's realistic gun building experience, with detailed customization options. 2. The app's user-friendly interface makes it easy to navigate and build guns. 3. The game's physics engine provides a sense of realism, making the experience more immersive. **Cons:** 1. Some users complain about the app's in-app purchases, citing high prices for premium content. 2. The app's lack of online multiplayer mode is a major disappointment for many users. 3. The game's graphics and sound effects are not as polished as some users had hoped. Note: The reviews are subject to change over time, and this conclusion is based on the available reviews at the time of my knowledge cutoff.