Checkout the announcement here.

http://blogs.zoho.com/general/announcing-zoho-projects-for-google-apps

How easy is it to use Zoho Projects into Google Apps ?

Short version: it's dead easy.
Long version: Here is a short video which explains the different possibilities for Google Apps customers to manage their project in Zoho Projects - all it takes is to login with our Google Apps credentials and off you go.

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