Q:

Making a web service, which approach?

I have made a Java EE 6 application where a user can browse a set of questions, add new questions and so on. The user can optionally log in so that he/she gets "credit" for adding the question or reporting it as bad. 
Now I want to make a iPhone application where the user can do pretty much the same. So the answer is web service I assume. I have not worked with web service before but I see there are at least to alternatives: SOAP and REST. 
Which one should I choose? I want the user to be able to log in from the application as well a as browse the questions in the database...pretty much many of the actions you can do on the web site.
I don't know much about the security and overhead they introduce.
Also I want the user to be able to retrieve the list of questions thorugh the web server and have the option to save it, so he/she won't need to have internet unless he/she wants to update it. Can I achieve this with both web services?

A:

You can take a look at this previous SO post for some guidance. I would recommend using REST, it seems to be less messy than SOAP and Java has support available for it as shown here.
Through the use of annotations, you can simply created a facade to which users will connect. In turn, this facade will call the relevant logic which I am presuming you already have.

