Web versus Mobile

[phumler]

Does the system handle displaying various sized images depending on the screen size?  For example, if it is on a wide web browser then it should display a large wide banner, but if it is a mobile device it will switch to displaying a smaller banner.  If not, is there a recommended way to configure this in the system?

[SMFHacks]

In a way yes. Would require two ads created.
When creating/editing an ad you have the option to
Show on Desktop Devices     
Show on Mobile Devices     

This is based on user agent.