I got the exact same results on every mobile device as on my desktop, it must have been only a caching issue.
There is no option to not have a default category value, but you can change 1 line of code to reset it.
Open wp-content\plugins\ajax-search-pro\includes\views\asp.shortcode.categories_terms.php and go to line 94, there should be this:
$selected = $cat->term_id == $style['default_category_selected'];
change it to
$selected = false;
Open wp-content\plugins\ajax-search-pro\includes\views\asp.shortcode.post_tags.php and go to line 93, there should be this:
<?php echo in_array($_sftag->term_id, $_sel_tags) || $k == 0 ? ' checked="checked"' : '' ; ?>>
change that to simply:
That should do the trick.Best,
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