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Until June 31st 2013 google will continue ActiveSync support for Gmail. Try this, to setup Gmail with ActiveSync on Lumia 920:
On you phone go to Settings > Email + accounts > Add account > Advanced
1. Enter your full Google Account email address in the User name field.
2a. Enter your Google Account password in the Password field. If you're 2-step verification user, use an application-specific password instead as decribed in step 2b. Otherwise skip to step 3.
2b. On your pc: i) Sign (gmail + password) in at www.google.com.
ii) Find and click the Account link (use the small upper-right down-arrow, near where you logged in).
iii) Click Security in the left menu, and then click Settings under the 2-step verification heading.
iv) After the second log-in, go to Administer Applications Specific Passwords.
v) Give it costum name (e.g. Lumia 920 Gmail ActiveSync) and click the Generate button.
vi) Voila, you have your password for step 2a.
3. Leave the Domain field empty. If your device requires you to enter a domain name, enter google.
4. In the Server field write: m.google.com.
5. Press Next.
6. Check Contacts, Calendar, or Email, depending on which you'd like to sync. (Tasks is not supported and will lead to an error if checked.)
7. Press Finish.
Really easy, right?! Now, lets hope the little babygirls MS and Google find out how to behave well before July 31st. (Someone please change their diapers, and supply them with honeyed pacifyers.)
You misunderstood, Google is ending support for AES which allows for syning mail, contacts and calendar through one account. For mail you can still use POP3/IMAP available through the 'Other Account' setup on Windows Phone.
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