I have the Skyradar portable ADS-B receiver, which connects via WiFi to my Ipad, and provides EXCELLENT weather coverage, and limited traffic info. I now live in the East TN area, and consistently get good ADS-B reception once I'm above 500' AGL.
I use WingXPro7 with the Skyradar. However, Skyradar also has its own APP, which is as good or better than WingX. The Skyradar also has its own WAAS GPS included. An internal GPS in the Ipad is not necessary.
I have now dumped XM weather. With ADS-B Weather, I have not had dropouts, nor had to send refresh signals, nor had to pay a monthly subscription fee. And, Skyradar customer service is superior - - - I could never say that about XM.
I bought the Skyradar receiver for the Weather capability. If the traffic function develops, great, but I bought it for the Weather (Nexrad, Metars, TAFS, Winds Aloft, Pireps, TFR's).
Bill