Please check the answer and comments of my previous question in order to get a better understanding of my situation. If I use Google DataStore on AppEngine, my application will be tightly coupled and hence loose portability.
I'm working on Android and will be using backend which will reside in the cloud. I need client-cloud communication. How do I build an application maintaining portability. What design patterns, architectural patterns should I be using?
Should I use a broker pattern? I'm perplexed.