The Mi Band 2 can show you some notifications, however very limited.
Get this on:
Amazon US: http://amzn.to/1YfPTFR
Amazon UK: http://amzn.to/24GM1Of
Amazon CA: http://amzn.to/1UlSVaa
For text messages you will get this notification:
For whatsapp messages you will see this notification:
For Facebook ans its messenger you will see this notification:
Instagram will also show you the above notification. There are probably other apps that may show different notifications on the band however, these are the only apps that i use and tried.
For incoming calls you will see the following notification:
The Xiaomi Mi Band 2 will show the clock the same as your phone shows the clock. If you use the 24h clock on your phone it will also be on your band. The following picture was taken at 3:02pm.