Here is a hack for you and others who want to have Gmedia Uploader on the Frontend:
Set capabilities for the user role in Gmedia Settings as following:
Gmedia Library – required
Upload Media Files – to allow upload media
Albums, Tags… – to allow assign already created by you terms (shared albums, categories, tags)
Manage Tags – to allow create new tags while upload media
Manage Categories – to allow create new categories while upload media
Manage Albums – to allow create own user albums (author for the album will be current logged in user. Other users can’t upload to others albums)
Then add iframe to your Page:
<iframe src="HTTPS://YOUR-WEBSITE-DOMAIN.COM/wp-admin/media-upload.php?post_id=0&tab=gmedia_library&action=upload&chromeless=1" frameborder="0" scrolling="no" width="100%" height="550"></iframe>
replace HTTPS://YOUR-WEBSITE-DOMAIN.COM
with your website domain url.