Freeboard.io - Free Open Source Real-Time Dashboard Builder for IoT

Freeboard is described as ‘A damn-sexy, open source real-time dashboard builder for IOT and other web mashups.’ Freeboard is an open source dashboard project with optional hosted subscriptions, easy to integrate with various data sources, ready for production, and very well designed.

Freeboard is a turn-key HTML-based “engine” for dashboards. Besides a nice looking layout engine, it provides a plugin architecture for creating data sources (which fetch data) and widgets (which display data)— freeboard then does all the work to connect the two together. Another feature of freeboard is its ability to run entirely in the browser as a single-page static web app without the need for a server. The feature makes it extremely attractive as a front-end for embedded devices which may have limited ability to serve complex and dynamic web pages.

You can find the free open source dashboard code here:
https://github.com/Freeboard/freeboard

If you don’t want to host the dashboard yourself, you can sign up for one of their subscription on their website.