If you want to configure the plugin differently for a mobile device then you need the plugin mobile content (need to register) or the plugin Mobile content switch.
These plugins allow to define different text inside an article based on mobile or desktop or more options.

With this plugin you can define for example:

{mosmap {mobile}height='250px'{/mobile}}

or the complete {mosmap} command:

{mobile}{mosmap height='250px'}{/mobile}

{desktop}{mosmap height='250px'}{/desktop}