Hope, iOS 12 has quite a few improvements and stable iOS than iOS 11. Even though the answer to your question may vary on case-by-case and different for different models, for instance, people ask Should I update my iPhone 6/6S to iOS 12? Should I update my iPhone 7/ 7 Plus to iOS 12? Since Apple’s all models have come up with different version chip (Apple A9, A10, and A11 processors) as well variance battery Mah Capacity as well device storage capacities including 16Gb iPhone, 32GB iPhone, 64GB iPhone, 128GB iPhone, and 256GB iPhone.
Get Here: iOS 12 Compatible devices list
Should I update my iPhone to iOS 12? Here’s Answer
By the Way, How old is your current device? If you have iPhone 5S then technically you can update your iPhone 5S to iOS 12, but your phone will run slowly. Because of its several years old already.
In More, Old models iPhone will degrade performance after iOS 12 update; While other side, iOS 12 is good for iPhone 8 Plus, iPhone 8, iPhone X, iPhone 7 (Plus), iPhone 6S/ 6S Plus, iPhone SE.
Second thing, are you waiting for new iOS features? Then you should update your device to iOS 12.
If you would like to download and install iOS 12 on your iPhone, then you can get the complete source in free on howtoisolve.com
Best suggestion for AR apps lovers: if you are an Argument Realty fan and want to touch AR apps and Game on your Phone then you must have Apple A9, A10, and A11 Process iPhone. Because A8 chip fitted iPhone won’t let you run AR applications.
You can sale your device or upgrade your old Apple phone to purchase high-performance hardware.