Is Google App Engine allowed for Commercial Use?
The complete Guidelines are below : http://code.google.com/appengine/program_policies.html
From what I read you can make use of the App Engine for business objectives. From what I read Google allows you utilize it absolutely free to get a preference wherefore it can do. There details use restriction is
An application on a free account can consume to 500MB of storage space and also approximately 5 million web page sights a month
So primarily it is free for any kind of usage regarded as lawful within their plans (no spam, pornography, etc) approximately the restriction. As soon as you surpass that you will certainly need to spend for your use.