Google will no longer be developer Google Gears, a technology that Zoho currently uses to make their Email and Word Processor Apps offline. No wonder, Zoho too is moving to HTML5.
At Zoho, we see HTML5 as the future of the web, and we plan to move our apps in this direction.
As far as Offline support for existing Zoho Apps (Zoho Writer & Zoho Mail, primarily) are concerned, they will continue to work for now as we migrate towards HTML5. We internally are experimenting with HTML5 and we are excited to see the possibilities. link.