Why can’t I sync Dropbox Sign with Drive on iPad?

If you're accessing the website through Safari, make sure that your Google Drive account and Dropbox Sign were integrated prior to you logging on with your iPad. You must sync Drive and Dropbox Sign from a computer first.

However, once you activate the Dropbox Sign and Google Drive integration on a computer first, the sync will work on the iPad in that you will be able to access your Drive documents when logged into Dropbox Sign.