If you worked with JSON, then you are aware of the cross-domain policy which prevents a script loaded from one domain, to invoke services from another domain. This means that the domain of the requested URL must be the same as the domain of the current page. A number of work around exists but one of the most popular once is using JSONP. JSONP allows a requesting URL from one domain to invoke a service from a different domain. Appery.io Mobile Apps Builder now supports JSONP. Why is this important? Well, it makes very simple to build and test mobile apps in Appery.io. Now a page can be loaded from abc.com domain and invoke a service from xyz.com. Most REST services today support JSONP.
To use JSONP is very simple. When defining REST service, select jsonp for Data Type:
To try this in action, try this Twitter Search app built in Appery.io.