Friday, 28 October 2016

Mi Band 2 features and functions reviewed

Its been a few days since I have this little gadget attached to my body and the experience has been fairly good. Here I list the features of Mi Band 2.

Time Display

Its marketed with a OLED display. The display is in white with good brightness but may appear  a little dim under the blazing sun. But then again, how much time is one likely to spend under direct afternoon sunlight? Incase of a normal bright daylight, the display has a good visibility with not problems at all.

Its most basic feature is of time display, one can choose between 24 hour time or 12 hour format. A lot people  miss this but hidden in the phone app is a setting that can be used to turn on the date and day display too with the time display.

Open Mi Fit app => Profile => My devices (Mi Band 2) => Time format => select the one with date

In the 'My devices' setting you can find the following features,

Find Band => Use it to check the connectivity of the band with phone by making the band vibrate.

Mi Band display settings => Can turn on additional display options like distance, calories, battery

Lift wrist to view info => This will turn on the display automatically when you lift your wrist. I usually don't use it as its known to drain battery.

Heart rate sleep assistant => This uses heart rate too in monitor sleep. Give more accurate sleep data.

Unpair => Will unpair the device from phone Never EVER click on it. As pairing can be pain.
In the 'profile' page you can also set activity goals (number of steps) per day and also weight goals.

Heart rate monitor

The heart monitor measures heart pulse rate using photoplethysmography. This technology uses red/green light reflection from skin to measure heart rate. The idea is, as heart pumps blood into your arteries, there is a very minuscule change in colour of skin when the heart pressure peaks (systolic stage) and when the pressure is reduced (diastolic stage). The LED lights of the heart rate sensor situated on the opposite side of display measures the rate of this colour change per minute. This gives you you heart beat or pulse rate. The technology used here is similar to the one used in hospital pulse measuring device. If you have noticed those rubber caps that are clipped on to your finger tips to monitor heart pulse rate in hospitals, they too have pulsing lights to measure heart pulse rate.

The green light switches on only when the heart rate mode is selected. The accuracy of pulse monitor sounds fairly good. I tracked the heart rate at normal rested state and it averages around 70 bpm and during high intensity workout it peaked 150 bpm.

One important note, heart rate monitor requires you keep your hand stationary to a reading to show up. If you are continuously moving you hand, it will not be able to measure the pulse. There is also an option to measure the pulse rate while running in the app at the top left corner. Heart pulse rate is also monitored automatically while you sleep to a better and more accurate sleep monitoring. This can be turned on as stated in previous section. Now it is noticed that the latest release of Mi Fit app (2.2.4) is known to give troubles in heart pulse monitoring and hence its advisable to install and older version of the app as recommended in my previous post,


A motion sensing pedometer that detects the number of steps you have taken the whole day. Based on the steps it calculates the calories burned. Talking about its accuracy, a test with around hundred steps it manged to give a fairly accurate reading of 101. That was indeed very good. Your daily steps are calculated and stored in history. You can compare all your data from past few days to months along with the calories burnt.

The running icon in the top left corner of app homepage allows you to start you run and measure the distance run along with the heart beat rate. You can also set the maximum heart beat rate below which you want to keep running. It will vibrate with an alert as soon as you heart beat crosses this maximum limit. You can also set a vibrate alert to let you know if you are running slow. 

Sleep monitoring

Sleep is in deed one of the most important factors for a good health and also one of the most ignored by a lot of people. Therefore, I think this is one of the most important features of this gadget. All you need to do is wear the band while you hit the bed. There is not need for the phone to be around with blue-tooth ON as the band will store the nights data and sync it to the phone whenever bluetooth sync is available.
The monitor registers the time of sleeping and time of waking up. It also measures the quality of sleep during the entire duration in the form of "light sleep" and "deep sleep". The sleep pattern is given in the form of a graph. You can touch on the bands to seep the time range of deep sleep and light sleep. It also tracks if you wake up in the middle of the night and registers the time and duration of the "awake" state. I tested sleep monitoring with two different people just to make sure if it does give different patterns, and it did pass the test. It generated a unique graph specific to the person's sleep.


It is recommended to turn on the feature of measuring heart rate while sleeping from,

My Devices => Heart rate sleep assistant

This will give more reliable and accurate data. Now, about how the band detects the difference between deep sleep and light sleep? It simply uses the accelerometers to sense very minute  movements of the hand while sleeping along with heart pulse rate. If you are still with low pulse rate then you are in deep sleep otherwise in light sleep stage.  You are having a healthy sleep as long as you have at-least 4 stages or bands of deep sleep amounting to a total duration of 2 to 4 hours in a 7 to 8 hour sleep. There are several ways you can try to increase you deep sleep state which I will dwell in my later posts. Experiments are still on.

Other features

There are several other features that are a part of Mi Band 2. Like, auto unlock of phone, call vibrate alert on the band, notification alert on the band for messengers like WhatsApp and an important one is a vibrate alarm that gently wakes you up without startling you. Ability to share you goals and achievements with your friends etc. The battery life has been very good until now, I have lost only 3% of battery in the last 3 days. Going good at 97%. Not bad at all!


  1. How do you get the app for a windows cell phone?

    1. There is an app called 'Bind Mi Band'. Out works pretty good! Not all features are there and sleep tracker costs 1,50 extra, but I downloaded it and it is worth the money.
      Separate app called "Notify Mi Band" can be used for the notifications for alarms and messages.