Class 2 - Generally used for Director KYC, MCA (ROC), Company incorporation TDS/ TRACES, Income tax, GST, Creation of DIN & DPIN, Provident Fund/EPFO & Government e-office.
Class 3 - Generally used for Tendering, eBidding, eProcurement, IRCTC Agent Registration (e-Ticketing), ESI/ESIC Registration, Patent & Trademark, Government e-office & Online PAN verification.
Document Signer - Generally used for bulk signing of invoices, claims, recurring bills, insurance policies etc.