Yes it is posible. I did that. You need to edit one of those php files in wysiwyg-editor directory. I dont have handy but I will get home in a couple of hours and get back and answer you.
Okay, here is the condition to use in your qa-wysiwyg-editor.php:
if (qa_is_mobile_probably()){...
for example:
if (qa_is_mobile_probably()){
$qa_content['script_lines'][]=array(
"qa_wysiwyg_editor_config={toolbar:[".
"['Blockquote'],".
"]".
", defaultLanguage:".qa_js(qa_opt('site_language')).
", skin:'v2'".
", toolbarCanCollapse:false".
", removePlugins:'elementspath'".
", resize_enabled:true".
", autogrow:false".
", entities:false".
", width:'90%'".
", height:150".
($uploadimages ? (", filebrowserImageUploadUrl:".qa_js(qa_path('wysiwyg-editor-upload', array('qa_only_image' => true)))) : "").
($uploadall ? (", filebrowserUploadUrl:".qa_js(qa_path('wysiwyg-editor-upload'))) : "").
"}"
);
} else {
$qa_content['script_lines'][]=array(
"qa_wysiwyg_editor_config={toolbar:[".
"['Bold','Italic'],"."['TextColor','BGColor'],".
"['JustifyLeft','JustifyCenter','JustifyRight','JustifyBlock'],".
"['Blockquote'],"."['Image'],".
"['NumberedList','BulletedList','-','Outdent','Indent'],".
"]".
", defaultLanguage:".qa_js(qa_opt('site_language')).
", skin:'v2'".
", toolbarCanCollapse:false".
", removePlugins:'elementspath'".
", resize_enabled:true".
", autogrow:false".
", entities:false".
($uploadimages ? (", filebrowserImageUploadUrl:".qa_js(qa_path('wysiwyg-editor-upload', array('qa_only_image' => true)))) : "").
($uploadall ? (", filebrowserUploadUrl:".qa_js(qa_path('wysiwyg-editor-upload'))) : "").
"}"
);
}