What exactly is a 棒棒机?
I know it's a simple, ordinary kind of cell phone.
Is it the same as the English: burner?
What constitutes a 棒棒机?
What equivalent phrases do we have in English?
Burner is not equivalent to, and not related to,
棒棒机 implies the form of the mobile phone – a phone that takes the shape of a cuboid, usually with rounded corners and/or edges.
Burner implies the use case of the mobile phone – a phone quickly disposed (burned) and replaced.
The English equivalent you are looking for is a
For more information, you can refer to this wiki page.
棒棒机 can refer to a category of smaller phones (usually the more rugged kind), typically used to refer to older model phones, particularly the bar-style phones.
In some areas of China, most notably the Sichuan area, they refer to 棍子 (cane) as 棒棒. It's likely that this has some relation to the naming. In other words, 棒棒机 can be referred to as an "old person/style" phone.
There's also 棒棒糖手机 which is used to refer to a specific model of LG flip phones. It's also worth noting that Android 5 "Lollipop" is referred to as 棒棒糖 as well.
Note that in some countries in Asia, smartphones are only now starting to gain popularity. The flip phone is still somewhat popular amongst consumers over there. China and Samsung for still seems to be have a love affair of sorts with flip phone, so as far as to release an Android flip phone.
You can refer to "burner" phones as 隐私手机 (privacy cellphone).