Follow along with the video below to see how to install our site as a web app on your home screen.
Note: this_feature_currently_requires_accessing_site_using_safari
Is this what you did? Through Wordpress.com??? (top of page) Products WordPress.com
What that is intended for is...
You get a free blog hosted on THEIR server and POINT your domain to them.
That's NOT what you want to do. Wordpress.com does not like blogs used for SEO or affiliate marketing. They strongly discourage affiliate links and could pull your blog after you take time to build it up.
But you should still own the domain. Like David said you need to find out how to get access to the name servers so you can point the domain to a hosting account on HostGator. Then you can get access to Cpanel and set up your own WP blog that you have complete control over.