The Sonoline B Fetal Doppler is praised for its accuracy, ease of use, and ability to monitor heart rate. However, some users found it lacking in features such as clock, calorie, and steps display, and others experienced issues with tracking sleep.

The Tune Bosch Fattal Doppler is praised for its ease of use, accuracy, and ability to monitor heart rate. It is helpful for those with heart rate issues and provides relief during illness. However, some users found the display display to be backwards and experienced tracking issues.

This oxygen monitor is praised for its ease of use, accuracy, and compact design. It is helpful in monitoring blood oxygen levels and heart rate. However, some users experienced issues with the device's accuracy, battery life, and durability.