Email, which is one of the oldest services available on the internet, is a key mechanism via which you can reach out to your users. Over the last year, the number of services providing this infrastructure as a service has grown to include 6 email sending APIs. The newest, Amazon Simple Email Service, validates the market.
Anyone who runs an app these days has no doubt attempted to handle all customer service through email. While this may be a great way to interact with your customers, it can get difficult to track just how helpful your email help is. That's where Nicereply and its Nicereply API can help. And it even has a brand new example app, the product of a little recent criticism.