Details surrounding OnePlus' next smartphone which could be the OnePlus 4 are already starting to surface, with rumors suggesting that the device could come with a total of 8GB of RAM as well as expandable storage up to 256GB. While these are just rumors and there is no way to verify them, especially considering the OnePlus 3 only recently launched a little earlier this year, things like expandable storage would be a huge improvement over past OnePlus devices as none of them have had the option to expand the storage beyond what was available internally, which, for their most current smartphone is 64GB, although for many that is more than enough.
Despite rumors of 8GB of RAM being available, what's more likely is that the OnePlus 4 could stick with the 6GB of RAM that OnePlus chose to use in their third and most recent flagship, as 6GB is plenty of RAM for what a smartphone is capable of doing, and if OnePlus is looking to keep the cost down and as affordable as possible (which could be around the $400 mark), increasing the amount of RAM could mean they would have to dial back on other specifications, or simply increase the phone's cost to account for higher-powered hardware.
In addition to the RAM and expandable storage options, it's also been rumored that the OnePlus 4 may come equipped with a 23MP rear-facing camera as opposed to sticking with the 16MP sensor that's currently available on the OnePlus 3. When it comes to the processor, there were no rumors mentioned here but as the OnePlus 3 features a Qualcomm Snapdragon 820 CPU inside, OnePlus could choose to bump the processor in their next flagship device to a Snapdragon 821, or they could go with another chipset entirely. As it's still really early there are also no mentions of battery life, screen size, or screen resolution, but at the very least the resolution is likely to be equal to the OnePlus 3 which is still Full HD. Whether or not OnePlus chooses to go with an AMOLED panel again for the OnePlus 4 is unclear, but new features such as Dash Charge could make a return, although there are no rumors mentioning this yet either. Speculation is that OnePlus could be looking for the OnePlus 4 to be a competitor for the newly announced iPhone 7, though, so whatever hardware they do use will need to be powerful enough to compete.