You can turn on messages from instant messengers, mail clients, social networks and even games.
Also Informer shows missed calls.
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For SmartWatch 3 we develop another app:
Informer Pro gives you premium options:
✔ Reply to messages from watch
✔ Add apps from your list
✔ Mute selected chats
✔ View images received by messengers
✔ Mark as read syncronization
✔ Set hours for night silence
✔ Mute when phone is active
✔ Filter unknown contacts
✔ Low phone battery alert
NOTICE: Turn Informer service on!
For KitKat or Lollipop: Settings > Security > Notification Access
For other versions: Settings -> Accessibility
Smart Connect extension for SmartWatch 2
LiveWare™ extension for SmartWatch