PlayStation 4 has received a system update. It is not a major update. As per the update logs, it is a minor system update that will add more stability to the console. The latest version is 2.55 it was released on July 1, 2015. Below is a link from where you can download the update. The update size is around 230MB approx.
PS4 is a popular gaming console. It is not having any major issues when it comes to gaming. That is the reason we do not really see much updates for this console. Compared to PC, consoles are lot more handy when it comes to gaming. Overheating is one of the most common issues still in these kind of consoles. And there is no direct fix for that. There are certain tips below that would help you to optimize performance of PS4 and also it will allow you to use PS4 for longer period.
Tips to enhance PS4 Performance:
Always keep the console updated with the latest System Software.
Defragging PS4 hard drive will give you better performance boost. And this can be done through Rebuild Database. You have to turn on PS4 in safe mode first. So to do that, turn off the console first. Hold the power button for sometime unless you hear two beep sounds. Using Dual Shock remote navigate to Rebuild Database.
From the same menu you can also select Initialize PS4. Or if the console has any major issue then you can go with the option called Re-install system software. But this will wipe all your games.