When you share too many files with others in your Google Drive account, you may lose track of who has access to Google Drive files. To see permissions for each file and folder on Google Drive Android app, do as follows:
1. Open "Google Drive"
2. Tap the Grey Arrow right to the File or Folder you want to check permissions
3. Scroll down and find "Who Has Access"
4. In this section you can see who is the Owner, who can view, edit or comment
5. Since you are the Owner, you can tap each person to remove or change Permissions