MOTO, Samsung and HTC all use 2-core mobile phones, and the price is around 5000.
IP4 will soon become an arcade, depending on personal preference. I don't pay much attention to Nokia now, so I can't give you advice.
I suggest you buy a mobile phone for about 2500 yuan, and keep the rest for other purposes. Now the price of mobile phones is very low, and it will be reduced in a few days. It is better to buy a cost-effective mobile phone. For example, Samsung's I9000 or Google's nexus S and so on.