Thingsboard allows you to configure customizable dashboards. Each Dashboard may contain multiple widgets that visuzalize data from multiple devices. Once Dashboard is created, you may assign it to one of your customers
Dashboards are light-weight and you may have millions of dashboards. For example, you may automatically create dashboard for each new customer based on data from registered customer devices. Or you may modify dashboard via script when new device is assigned to customer. All this actions may be done manually or automated via REST API.
You can find useful links to get started below: