Ok, so you created an app...
Make sure to have created a private key, and to sign your app with it! This is done on the IDE. (The private is unique to each app, and will be needed for any upgrade/upload of your app)
If you haven't already created a Google Developer Account, do so... They will charge your credit card about 30€ (single fee) and in a few hours you will be ready to publish your app.
When uploading your app, Google Services will proof your app and warn you if something is not in accordance with the Services Policies. Then, if all goes well, after a few hours the app will be live!