The paper proposes smartphone applications, that allow doctors to continuously observe the main organ of patients, affected by the coronavirus, -the lungs. The applications are based on wireless devices and designed in a way to monitor the state of patients' lungs round-the-clock and regardless of their location. Therefore, created applications allow the doctor continuously and remotely (e.g. from their office) see the level of oxygen in the patient's blood. These data from the pulse oximeter with a wireless connection will be send via the patient's smartphone to the server, where the doctor will receive information about the patient's condition and can decide on further treatment. With these applications, doctors will be able to monitor the condition of their patients, who are in hospital wards as well as at home, on observation or outpatient treatment. What is important, this way it will be possible to track the condition of the sick not only with Covid-19 but also with other diseases, for example, asthma, vascular diseases or cancer.