The following resources will provide you information to get your trending application put together quickly for Smartphone clients.
View the following video for a quick introduction to OPC Web Trend.NET.
View the following video for basic steps on using OPC Web Trend.NET in a web application.
For setting specific real-time time frames for trending view the following video.
Other resources for web trending applications.
View the Networking video for syntax on how to enable remote communications if your web application will be running on a different computer than the OPC Systems Service.