At 67 years, I am more conscious of my blood pressure and heart rate since I have had issues before. I can check my heart rate directly on the watch, but not the blood pressure. The app is needed for that, and it is well worthwhile. Not only can I check my blood pressure, but once the watch and phone are synchronized, the app shows hours worth of both blood pressure and heart rate measurements on separate charts. Very cool! It also monitors my sleep and blood oxygen levels.But how accurate is it? So far, the watch seems to read up to 10-15 points high on the BP and up to 10 points high on the heart rate. This is no problem as long as I know to allow for this when reading the daily charts. Included in this review is a sample BP chart.The sleep monitor matched what I expected. I don't get much deep sleep, mostly broken light sleep. I have no idea how accurate the blood oxygen levels are.I love the large screen size and variety of faces, or "dials" available to match the users' preferences.For the $129 I paid, this watch is a real bargain.