In the world of "warez" and software piracy, a "Grindr Premium IPA" is a modified version of the original app. Hackers and developers take the official app, decrypt it, inject code to bypass subscription checks (often called a "patch"), and repackage it. The result is a file that, theoretically, installs on an iPhone or iPad just like a regular app but behaves like a paid subscription version without the cost.
If you have already downloaded a Grindr Premium IPA, take the following steps immediately: grindr premium ipa