If you enable GCM at the domain level you can disable GCM for a specific domain by removing the
routes and the
delivery_method options from the scope where you wish to disable GCM. In “Configuring for GCM” all you need do is remove the GCM-related options from any Google push domains that you have defined. (Note: Apps are domain-specific so if you need to disable notifications for a specific app, disable the appropriate domain.)
If you have some domains that are GCM enabled and some that are not, do not configure GCM-related options in a global context (excepting the HTTP options shown at “HTTP Protocol Configuration” which are identical for all domains). Only set them within the domain scope as shown in “Configuring for GCM”.
To disable GCM entirely, remove the
gcm module, the gcm_logger module and any options used to configure GCM.