Mobile App Services Azure. I understand there is really no. Blade with following details will appear.
Azure app service enables you to build and host web apps, mobile back ends, and restful apis in the programming language of your choice without managing infrastructure. Click ‘+’ sign => web + mobile => mobile app. Blade with following details will appear.
Once you have an azure account, just log it in the azure portal and you should now see your azure.
To answer your question specifically, azure web app is new name for azure websites that you can use to build websites in multiple languages where as azure. Azure mobile apps is a feature of azure app service. Store data in azure cloud storage. Azure cognitive services add smart api capabilities to enable contextual interactions;