The original forum address advertised promo codes for iDocs Pro for Google Docs and Google Drive. A December 2012 app listing corroborates that title and its document-management purpose. No valid giveaway codes or continuing offer were recovered. The useful underlying task remains preparing documents to work with on an iPhone.
Which files need to travel with you?
Choose a short list before leaving a reliable connection: the itinerary, meeting notes or draft you expect to edit. Check the account and file names so that similarly titled documents do not obscure which version matters.
Google’s official offline instructions cover its Docs, Sheets and Slides apps. Beside a specific file, open the More menu and choose Make available offline. The apps also offer a setting for making recent files available offline, but a deliberate selection is easier to audit for an important trip.
How do you check that preparation worked?
Open the app’s Offline section and inspect the intended files. Read beyond the title: make sure the document contains the material you expected. Do this while the original account and a connection are still available to correct omissions.
A quick rehearsal is useful. Decide what you will need to read and what you will need to change, then try those tasks with a nonessential document. A successful preview of one file does not establish that every other required file is ready.
What happens to edits afterward?
Google’s file-saving guide says offline edits save on the device and reach Drive after reconnection. Allow that reconnection to happen before expecting collaborators to see the result.
After returning online, inspect the document from the account where it belongs. Avoid creating several differently named copies merely because an update has not appeared immediately. A clear source document and an observed sync result make the next editing session much less confusing.