My IOS app will be used daily, An image and some data will be displayed to the user and will be saved not to connect again. So an user will use approximately 30kb per day.
Now, for testing, I'm using a basic hosting plan for MSSQL and Web Service. On SQL Server, I have 4 tables and an average of 5 columns (I mean It's not a complicated database)(and also I have a subquery). And I'm using .net web service for communicating from IOS app. And lastly, one image for one day is hosted.
I've tried to explain basically but It's expected to reach at least 1 million user after a short period of time according to my big clients.
So I want to start with AWS not to fail but really I don't know which products/settings do i need (from few users to millions) and how to start to AWS EC2. Also I want to specify that after AWS's documents and googling, I'm confused.
Please show me the way.
You want autoscaling both in the webtier and in database resources. You also likely want high availability (i.e. trans-AZ, trans-regional deployment). This answer might help point you in the right direction. Start with ElasticBeanstalk and RDS (if you can afford it). They both abstract out huge swathes of autoscaling.
Also pay close attention to the ElasticBeanstalk architectural overview. It'll help you distinguish between the web tier of your application, any application layers, and the database layer of your stack.