Apps not working on guest wifi

I have had my Samsung Galaxy s3 4g for 2 weeks and am new to smartphones. At home I have no problems. But seem to be having difficulty using apps while at other locations. Was at Falcons game and connected to Georgia Dome WiFi but when I tried to use the Delta App to check flight schedules it would not connect even though it showed that I was connected to their WiFi. Again while at a local hospital I connected to the guest WiFi and although I could check email and surf the web "Words With Friends" would not update plays until I got home. It seems that I can connect to guest WiFi's but the apps will not work. What do I need to do.
Please Help.