Compared to the Raspberry Pi 3 Model B+, the Raspberry Pi 4 Model B delivers a major boost in performance and capabilities. It features a faster processor, improved graphics, more RAM options, and better connectivity such as USB 3.0 and Gigabit Ethernet. These enhancements allow the device to perform tasks similar to a desktop computer, including media playback, gaming, and software development, while remaining compact and power-efficient. This makes it suitable for both hobbyists and professionals needing a powerful single-board computer.