Here’s a little tip that’s not particularly brilliant, but just useful, as you start working with the new application model in SharePoint 2013. You always need a subscription settings service application, but it’s one of those things that you cannot create in the UI. So just keep a bookmark to this post and come back as needed for a little copy and paste. This brief PowerShell snippet will create service application and proxy in one fell swoop:
New-SPSubscriptionSettingsServiceApplication -ApplicationPool "SharePoint Web Services Default" -Name "Subscription Settings Service Application" -DatabaseName "SubscriptionSettingsDB" | New-SPSubscriptionSettingsServiceApplicationProxy
Once you’ve created the Subscription Settings service application, you can go configure your application domain in Central Admin.