Yes, those are the same things. You will either read from a characteristic or write to it, which translates to receiving and sending data respectively. So it would be the same procedure.
Is there a reason that you wouldn’t want to use the Particle cloud? I will say this, even if you are writing an app, it may be easier to use the cloud. This way you don’t have to worry about low-level bluetooth tasks and can get data from bluz through the simple REST API. This may be easier than trying to write an app to talk directly to bluz. The one downside is latency, it would clearly take longer, but if that isn’t a huge concern, you could still use the Particle cloud.
We will support both, just the latter part isn’t available today.