With Babybeat Tracker you can measure fetal heart rate by using your phone's microphone. How is it possible? It works like a stethoscope. With stethoscope you can hear the baby's heart beat at about 18-20 weeks. During measurement heartbeats are drawn. After the heart rate is measured, corresponding simulated fetal doppler sound can be listened. Heart rate can be measured in two ways. The first way is to position the microphone like a doppler device (on your belly). Quiet environment is needed. This measurement way can be used from about week 27, but every pregnancy is individual. Fetal position also affects to how easily heart rate can be measured. The second way is good if you own a home doppler, but don't know fetal heart rate. Pulse can be measured from pre-recorded doppler audio or directly from home doppler's speaker. Important note when measuring directly on belly: So far all WP 7.8 reviews have been very positive whereas users have reported problems with almost all the WP8 phones containing several mics (Lumia 620, 720, 820, 920, HTC 8X etc.). However, heartbeat can be detected with those phones if heart rate is measured with the top microphone. Try Babybeat Tracker with your phone and give feedback. Trial version contains full functionality. Buy app to get rid of ads. Features: + Calibration to adjust microphone sensitivity according to the used phone + Visible heartbeats can be monitored + Simulated fetal doppler sound is generated after the heart rate is measured (it is not real recording) + Measured heart rate can be saved to results + Live tile shows the last measurement + Airplane mode detection and turning on Babybeat Tracker is not intended as a replacement for medical advice. For any medical questions, consult your doctor or midwife.