What is the range?

There are several factors which affect the range.  The app  doesn't care whether you are 10ft or 100 yards away, it is simply looking for the red laser to show up on the target.  Lasers can go for hundreds of yards and still be seen - so it becomes a factor of how bright that laser is when it hits the target.  Unless you live in a very large mansion, you won't hit the limits of range unless you are outdoors.  Being outdoors creates an additional problem because sunlight on the target washes out the laser light hitting the target and makes it difficult for the app to distinguish the laser mark.  It will work outdoors, but it must be in the shade.  At night, it would likely work for over a hundred yards.  It's been tested it at over 25 yards by shooting from the yard into the house.