Ranked in these QuestionsQuestion Ranking
Pro Increases application speed considerably
Google App Engine integrates with Google's CDN out of the box and it distributes your application's assets through that, increasing loading speed considerably.
Pro Easy to use
Google App Engine is very easy to use. All you need to do is install the SDK (which in itself is easy as well, and the documentation is very heplful) and run the command needed depending on the type of project to deploy it.
For example, to deploy a golang application, you run
golang deploy inside the project folder and it will be automatically deployed.
Con Not a core Google product faces uncertin future
Google is notorious with flipping on technology directions, this product is clearly not the focus of Google.
Con Expenses are very hard to control
The monitoring for expenses is limited at best.
Con Problematic support even in the paid grade
Con No SQL database available
Google App Engine uses Google's NoSQL cloud database. There's no option to use a SQL database with your application.