Google Drive is a cloud service that provides 5GB of free storage to consumers. Anyone with a Gmail account also has a Google Drive account with 5GB of storage. Additional storage may be purchased or earned via purchases of Chrome OS devices. Google Drive integrates with Google services like Google Docs, Gmail, and Chrome OS. You can store, edit, and create a variety of file types from within the Google Drive website, the Google Drive app for iOS and Android, or the Google Drive desktop folder for Mac/PC. A number of mobile and desktop apps integrate with Google Drive, including iAnnotate for iPad.
iAnnotate supports integration with Google Drive for importing documents and backing up your work. A connection between iAnnotate and your Google Drive account allows you to browse your entire Google Drive folder structure from the iAnnotate library, download applicable documents and folders, and upload documents back to Google Drive after you have marked them up. However, it does not allow you to actually modify or reorganize how your Google Drive is set up, with the exception of moving or copying documents from iAnnotate to Google Drive.
Connecting to Google Drive
Navigate to your iAnnotate Document Library (by tapping the Library button in the upper left) and tap Connections in the Library navigation panel. Tap "Add Google Drive" and enter a description (it defaults to "Google Drive"). Enter your Google Username, typically your email address, then tap "Set Up Connection." Choose "Read Only" if you want to use the connection to import files, but wish to disable syncing annotated files back to your Google Drive account. With this option turned on, your annotations will only be saved to your iPad and not backed up to Google Drive.
Now find the new Google Drive connection icon in your Library, it will appear light gray meaning you have not downloaded anything from it yet. Tap the icon to continue the setup process. Your username will already be entered (if you've made a mistake and mistyped this you will need to delete this connection and make a new one since you cannot edit the username in the authorization window). Enter your password when prompted then tap "Sign In." You will then be asked to allow iAnnotate access to your Google Drive contents. Tap "Allow."
Downloading and Managing Files
The connection between Google Drive and iAnnotate lets you download documents in PDF, DOC, GIF, JPEG, PNG, or PPT format. To download a document, simply tap on it, or tap and hold then select Download from the popup menu.
Upon modifying a document from within the Google Drive connection, the sync icon in the upper-right of your screen will turn red to indicate there are un-synced changes. Tap the sync icon to upload the changes back to Google Drive immediately; changes are uploaded automatically when you close the document tab.
Deleting any document from iAnnotate does not also delete it from your remote Google Drive account. The document would still exist in Google Drive, in its most recently modified and synced version.
You can move local documents into your Google Drive account from iAnnotate. To do so, tap and hold a document in the iAnnotate PDF Library, then tap Move and select Google Drive from the list of target folder options. Alternatively, you can select multiple documents using the selection circles next to them, then tap "Move" in the Actions accordion at the left of the Library. However, you can not move whole folders from iAnnotate into Google Drive.
You can also copy a document from your Google Drive account into local storage on your iPad. To do so, tap and hold a document in your Google Drive folder within the iAnnotate PDF Library, then tap "Copy" and select Local Files from the list of target folder options. This creates a copy of your document that isn’t synced to Google Drive.
Viewing Markups Sent to Google Drive
When iAnnotate syncs with Google Drive, it sends the marked-up documents as annotated (non-flattened) copies, meaning that their markups are not compressed into the document but rather occupy a “layer” on top of it. As such, they are best viewed in compatible Mac/PC programs like Preview or Adobe Acrobat/Reader. Editable annotations will not be viewable in most mobile (iPhone/iPad/Android) apps, web browsers, or on the Google Drive website.
For broader compatibility, use the "Flatten PDF" button in the Library to create a copy with the annotations compressed into the document.
Known Issues with Google Drive
Google Drive allows for the creation of documents in a number of formats that are not currently supported by iAnnotate. These formats include Google Docs, Google Sheets, and Google Slides, as well as any drawings or other plugins used with Google Drive. Any document saved to one of those formats will not be displayed in the Google Drive folder structure in your iAnnotate PDF Library.