One of the larger commercial projects for a hospital - the task was to develop a standalone ECG monitor that patients could wear at home for a standard Holter test. Previous monitors were bulky and required a Bluetooth connection (on a separate smartphone with special firmware and app) to wear at all times. This project was very challenging firmware-wise and assembly-wise, but also logistically - we had to go through several iterations, tried new technologies, and on of the major problems was testing. More on that further. Patients that undergo this test are usually elderly and can forget or do not know how to use a smartphone app, and wearing two devices, as well as possibly your standard smartphone is really too much to ask of any person. But the idea itself is very useful - realtime monitoring of a patient's heart condition can be lifesaving, even not counting the Holter test data itself. For that, the device needed to be standalone, as convenient and simple to use as possible and have reliable functions and stable connection to server.