* Any rig that has rig control software running on a local PC.
Step 1 (Rig Audio)
Use your radio interfaced to your home PC with an interface from MFJ or West Mountain Radio and put Skype on that PC. Set up a Skype account name for it. Load Skype on your cell or tablet. Set Skype on your home PC to auto answer and only take calls from your phone and/or tablet. Place a call from your cell or tablet to your home PC (the one hooked to your radio) and ensure the home PC answers automatically. You should be able to hear rig audio and your voice over the cell should modulate the rig. In fact, if you set up your rig's vox, you should be able to operate remotely using vox. The com port cable to the interface should be disconnected.
Step 2 (Rig Control)
Download "Tightvnc" http://www.tightvnc.com/
and install it on your PC running the rig control software. Install "VNC Viewer" or "Mocha VNC Lite" on your tablet or cell phone. Reboot the PC. Run the software on your PC to control your rig connected to the radio com port. Make sure it works. Configure your cell phone or tablet to get to your PC on the network (from command prompt run "ipconfig" so you can see what the PC's network address is). Enter that address in the cellphone or tablet VNC software.
Connect to your home PC by running the VNC software on the tablet or cell phone and you should see your computer's desktop like you were sitting in front of it. Now you can change frequencies, use features and PTT. I use a timer to turn my amp on and off that I bought from Amazon for $9.
Skype provides the audio link to your rig. Your PC rig control software runs on the desktop to control the rig. A VNC connection allows a cellphone or tablet to control the desktop remotely and therefore control the rig control software running on it. Below is my iPad with a mike and earphones with the Kenwood 2000 control program running on the screen. It is hooked up VIA the network to my PC at home which is running Skype and TightVNC. I am using Skype in the background on the iPad and MochaVNC Lite to see my PC desktop at home.