if you are looking to sync your Facebook contacts with Nexus 7 contacts, then you can download Facebook contact sync app from Google play.
To sync your Facebook contacts with Nexus 7, follow below mentioned steps:
1. First navigate to Google play store on your Nexus 7.
2. Now search Facebook contact sync app.
3. Once you find this app, download and install it.
4. Now move to Settings.
5. From here select Accounts & Sync.
6. Now click on Add Account and enter facebook account details.
7. Now check on Sync Contacts checkbox. Also provide the frequency for sync you want.
So by following above mentioned steps, you can sync your Facebook contacts with nexus 7 contacts.