The visual appearance of a colony in a cell culture requires significant growth, and when counting colonies it is uncertain if the colony arose from one cell or a group of cells. Expressing results as colony-forming units reflects this uncertainty.
The colony counting problem can be easily solved by using the "CountThings By Camera" mobile app. You only need to take a photo, click to identify, and the whole process can be automatically completed, and the accuracy can also be adjusted.
You can download it at google play named "CountThings By Camera"
