WhatsApp - Online Monitor is a free Chrome add-on that allows users to receive notifications when a contact is online in the WhatsApp Web App. With this add-on, users can easily keep track of their contacts' online status without having to constantly check the app.

The add-on includes a popup page that allows users to select which contact they want to monitor. Once the monitoring is triggered, users will receive notifications whenever the selected contact is online. This feature is especially useful for users who want to stay updated on the availability of specific contacts.

WhatsApp - Online Monitor is a convenient tool for those who want to keep track of their contacts' online status in the WhatsApp Web App. With its easy-to-use interface and notifications feature, users can stay connected and informed without constantly checking the app.