If you are a skills developer (or just registered on the Amazon Developer portal) you may have recently received an email from Amazon advising that you have received $100 in credits for the AWS service. This isn't a one-off piece of generosity from Amazon. It is actually much more.
Amazon has instigated a program that will essentially make running their skills on AWS a free prospect. Once the free credit is exhausted you can register to receive further credits. This new scheme makes AWS a much better proposition that using your own server or hosting, especially if you do not need to call any information you store yourself. For example, I currently host my own skill that calls a 3rd party API. I do not store the requests or results, this skill can now easily remove my server from the equation calling the API directly from Lambda. I can also setup to store the results and requests and be safe in the knowledge that I will not pay a penny.
For more information on the scheme check out Amazon's official post.