I contacted Samsung about this and they confirmed that IBI data is still collected when the screen is off, but the delivery method changes to save battery. Instead of streaming in real time, the data is gathered with 1 Hz frequency in the background and delivered in batches every few minutes.

If you need to access the data sooner than the system delivers it, the flush() method can force an earlier update, though it may impact battery life.

In my own testing, I found that the IBI data collected when the screen was not on, was inaccurate and for my use case, not usable. This might vary depending on the device but it’s something to consider if you’re relying on high-quality data.