
Easy interface, a webapp not a mobile app. Easy CSV mail importing. An effective scheduling option for recurring cards. I mainly use it personally, but it's a cute business solution overall for small businesses or folks with a few clients. It is very easy to fire off a thank you from your phone on the go. Review collected by and hosted on G2.com.
Postable is definitely not designed for work at scale. It clearly targets the consumer segment, so if you have 500 sales contacts to bulk mail, you will have a hard time. As near as I can tell they always do a first class stamp and charge you for that. If you mass mail or do marketing mail, I don't believe you get a presort rate which is an issue. If your use case is executives or sales reps firing off 1-5 cards on demand it works. Review collected by and hosted on G2.com.