Abstract. The recording of fetal heart rate can be reassuring for the mother about the fetus' wellbeing. Our smart phone application can detect, record and evaluate fetal heart rate at any time. This method is radiation-free, and can be used all day without harming the fetus. It does not require medical assistance and easy to use at home. It reduces the queue at outpatient care units, helps pregnant women to relieve stress by listening to their unborn baby's heartbeat. It improves mother-child relationship yet sends an alarming message if further examinations are needed to prevent the consequences of hypoxia.

Atrial fibrillation is the most common sustained cardiac arrhythmia. To determine the main frequency of the atrial fibrillation the frequency-domain analysis is used mostly, however it is unreliable in several cases. This insufficiency led to the demand of using time-domain analysis. Although these attempts seemed to be promising, there have remained several limitations. In our research we developed an enhanced algorithm for time-domain analysis. We defined two indicators which characterized the signals and the reliability of the method well. As compared to the frequency-domain analysis our algorithm can widen the applicability of time-domain analysis since in several caseswhen the results of the frequency-domain analysis are unreliableit can be applied still reliably. As a complementation of the frequency-domain analysis our algorithm can be an extremely helpful tool in medical practice. I.