How can I use webservice to search the messages that are scheduled> now (), and those that have been sent in a certain period (between)?
Douglas,
It seems that playsms webservices doesn´t have this option. It would be developed.
Did a look at “query” webservices, but I think it doesn´t solve the problem.
If do you need development, feel free to call me. My skype is espessoto, and I am brazilian also. 
Edilson