The Raspberry Pi 3 Model B+ also has faster ethernet at 300 Mbps. Additionally, it introduced an all-new Power over Ethernet (PoE) support (users need to buy a separate PoE module, though).

If you're in the market for a Raspberry Pi, the main reason why you'd want a Pi 3 Model A+ is its smaller board size. It measures by 0.33 by 2.6 by 2.2 inches (HWD), compared with the 0.63 by 3.5 ...

Pi 3 Model A+ – Like the Pi 3 Model B+ but only one USB port and no ethernet port. Pi 4 Model B – Two micro HDMI ports, USB-C power, and four USB ports (two black, two blue).