A budget phone is inexpensive and designed for a mass audience. That is, almost everyone can afford such a device. Such a smartphone will not be distinguished by its powerful processor, high-quality display, frameless design, and very good camera. It will also, in most cases, lack NFC, fast charging support, and 5GHz Wi-Fi.
But despite this, such a device is quite comfortable and runs modern applications and simple games. For social networking and the Internet, such a phone will be enough. Yes, the applications will not open lightning fast, and there may be minor interface freezes, but the low cost of the smartphone covers all these shortcomings.
If we are talking about Xiaomi phones, the most budget lineup is Redmi. In such devices are installed medium-power processors, good screens, and fairly normal cameras. Of course, the body will be plastic, and a slightly noticeable frame will be around the display.
More to the budget or medium-budget range can include the smartphone series Redmi Note. Here the phones can be equipped with fairly good processors, large and clear screens, and even NFC. The body can be made of both plastic and glass.