Heart rate monitoring devices have come a long way over the years. Plenty of smartwatches now allow you to monitor your heart rate without having to wear a chest strap. Heartomo happens to be a wearable heart rate monitor that combines with your smartphone to track your heart rate 24 hours a day. This miniature heart rate sensor weighs only 13 grams and does not get in your way. It maintains your data in the cloud and helps you catch problems before they become something serious. Use it to determine any disturbance in your heart rate and analyze heart rate fluctuations. It sets you back around $200.