Offline eKYC refers to uing either eAadhaar or QR code to authenticate an individual. The eAadhaar is a Digitally Signed PDF that has the individual's information as available in the Aadhaar database. This PDF also has a QR code that has the same information (and which can be scanned and verified by mobile apps developed by UIDAI). There is also an XML equivalent (instead of a PDF format), which allows faster processing by automated algorithms.
The eAadhaar PDF as well as the XML are downloadable by the individual from the UIDAI website.
Automated API for processing eAadhaar PDF or for processing the XML ("paperless offline eKYC" as UIDAI calls it) are now available from Truecopy. For more information, email email@example.com