I am new to phonegap.I have used web API in my code but it's giving "error O"(android emulator on windows).What i shuld do now?? How to rectify the problem??thanks in advance

Can you suggest me some links,books about mobile communication(with servers)regarding above question?

Suppose I want to send a message to mobile from my website across the world(irrespective of service provider),then what I need to do? Do I need to develope my qwn code or I just need to use the available services??

Also I would like to know if any type of mobile service exists??(for example message only,call only etc)

Thanks in advance.