can the quad core mali 400 run all the android games at high graphics
Hi Wavywessxx,
Your question is very broad as a Quad Core Mali-400 GPU is not only in one device but a vast amount. Many factors dictate whether an android game will run on a device at all even before settings such as high/low quality are taken into account. As an example form factor, e.g. tablet, phone or watch etc. as well as other factors such as resolution can all vary though all using a Quad Core Mali-400 GPU. It is up to the developers to optimise their code and they also have the option to dictate whether their application will be listed as incompatible with specific devices in Android stores. Having said that if optimised code is used high-end graphics can definitely be achieved on a Quad Core Mali-400 GPU.
If you have a specific device and application you are curious about let us know and we can investigate further. You can find more information about Mali-400 at ARM Mali-400 Overview