Is there an offline Google docs app?

Option 1) For offline access, open Chrome. Click the Google Docs app icon or visit https://docs.google.com The offline version of your Documents List will load.

You may need to add google docs to your Chrome - https://chrome.google.com/webstore/detail/apdfllckaahabafndbhieahigkjlhalf

Option 2) Use a text editor - gedit or LibreOffice, edit the document(s) then save them in your Documents folder. Then, when on-line again copy the info into a google doc.