Auto SMS Reply
A great feature which would help users very much is auto reply SMS.
Let's say your phone is off for meeting or you are on vacation, but you need to turn on Auto SMS so clients get auto reply, just like auto reply in emails or vacation response. That way we receive message and client gets auto reply.
Khurram Qureshi commented
Also I noticed that in Apple SMS has feature like if you first send SMS, it auto reply you with particular greeting, like thank you fore reaching xyz/abc person. But when conversation starts, it does not send that message again.
So for first reply it is good to have Auto Greeting or Auto Reply, when you join the conversation then it works like normal.