Best way to have contact update their own info AND control the update.

Best way to have contact update their own info AND control the update.

Best way contacts can update their own information? I understand I can email them a link to a form. 

I'm really asking about the approval process after. Once they've updated, how should we set up checking the updated info before it goes into the system?

Can Zoho Approval do it?
Or do I make extra fields "updated phone number, undated address" etc and transfer them over?

How do I control it on the back end? Make sense?