Arduino YUN, Bluetooth, Xbee, and Wifi Questions

Hello Friends,

I am working with the Arduino YUN, Bluetooth, Xbee, and Wifi to accomplish my goals for the sensor project I'm working on. Now,that is not to say they are all being used simultaneously. I am trying them out individually to get the best working solution.

Here's what I know. I know I can communicate with my Arduino YUN over the WWW and therefore affect my Xbees long distance.

I also like the way I can interact with Androids apps to communicate with the Bluetooth connected to Arduino to affect it as well, and anything connected to it.

What I don't know is whether I can communicate with my Arduino YUN + Bluetooth over my wifi or my computer with a USB Bluetooth chip by using my Android app on the other side of the earth. I don't have enough experience to know this personally, and the searches I have made on Google don't seem to be illustrative of this.

If anyone can enlighten me about this I would so appreciate this so I don't waste time on technology that may not be best suited to my needs. Also too, I am not interested in paid for Web sites to aid me in the communication process.

Thank you in advance,
houdinihar