contact sync with two different device iPhone and android.

hi

kindly advice me on following points:

1) is it possible to sync our contacts on iPhone and a android phone.

2) if we add a new contact to one device will it be automatically added to other device with same Google account.

3) if we delete or edit a contact on one device will it get automatically deleted or edited on other device with same Google account.

4) is this a safe way to have a contact back up as i had lost contacts as i had to reset my iPhone to factory settings, and my all contacts on Google did not sync many got deleted automatically.