Cardiographs: Heart rate pulse

On my iPad which has no flash drive, this will not complete a reading. Too dark it says. Moving to a brighter location does no good. It should state you REQUIRE a flash drive in order for it to work. My husband has the iPhone with a flash drive and it works very well. If this worked without the flash drive, I would give it a 5 star.

Only 17 about Cardiograph Classic, v2.5.4