IPhone4 and previous models don't support Bluetooth 4.0, so they don't support mi band and most other low-power bracelet products.

After downloading and installing the Xiaomi-specific APP in the app store, mi band can use it to check the amount of exercise, monitor the sleep quality, wake up the smart alarm clock and so on. You can check the amount of exercise in real time through the mobile phone application, monitor the effect of walking and running, and identify more exercise through the cloud. Mi band can automatically judge whether to enter the sleep state, record deep sleep and shallow sleep respectively and summarize the sleep time, thus helping users to monitor their sleep quality. Mi band is equipped with low-power Bluetooth chip and acceleration sensor, which can stand by for 30 days. In addition, it supports IP67 waterproof and dustproof, which means that you don't need to take it off in your daily life, even in the shower.