Do I have to manually switch off ATT network in my iPhone 4 before it uses my home wifi through my ISP?

This is the same thing I told to ATT folks when i found that they thought I over used my data plan. I read newspapers from safari browser, watch You Tube, my kids download games when we are at home. I see both wifi sign and ATT network sign active. iPhone4 is a smart phone and I know that Steve Jobs will be very unhappy from heaven about this 🙂.

The support person from ATT says that even she has to switch off the ATT network manually to ensure that she won't be charged for data plan. I told her that if this is the case they should mail or text to subscribers because I am sure that millions of users are thinking what I am thinking about this. They should not be charged when they use home wifi.

Choise of the Network channel is upto the Transport and layer of the communication. Why should we handle it in app layer.

That is because when apps request data transport the logic of deciding how to do that transport is not in the app it is in the OS and its trasnport layer. It does not make a difference which app goes through the ATT network or wifi. Because irrespective of which app I use the transport layer should have handled the problem sameway. If there is a problem in the phone/OS or the network provider that my data requests still get routed via ATT network when I am at home and using Wifi then it is a different problem. iPhone is a smartphone and I know that iPhone detects hotspots automatically when I am on the road or enter into a mall, airport or cofeeshop. This wifi which I am talking about is hard coded to my phones settings which means that phone should not have any problem in detecting it. If that signal is active it should use that. Why should it consume my data plan usage?

I am not talking about my phone being a Wifi sorce. in this case it will not be the signal source and should not consume my battery when the browser is not being used or when it is sleeping.When I start using the phone it knows that it is off the sleeping mode and then try to connect to the internet using my wifi. The wifi source is my wireless router. So it uses its energy from the homes power supply. It should not be a problem for my Cell Phone. Cell phone should worry about wifi signal when it is being used. When my hands are off it should not matter.

how can I explain why should I not worry about which app uses data without explaining what happens during the data transport ?

I would re-charge my battery if it is running out of power rather than having to pay the price as twice as a new battery for my overusage of internet because my phone attempted to save my battery. Data plans are expensive than the battery. So why bother about the battery, Besides my phone is not acting as a wifi source. What you say may be true when you use your phone as a wifi hotspot to enable internet to other things like your iPad. But in this case wifi source is my land line internet and the wifi router.

yes I have a 200MB plan. I do not use it that much when I am outside of my home. I keep the data plan for an emergency. When I asked ATT to check when was did the high usage happen they told that even if my wifi is active at home, it uses my ATT network unless I goto settings and switch off Cellular data manually. This is not what is expected from a smart phone. When I drive to places my phone randomly ditects wifi networks and ask about switching to that. If that can be done why can't it do it to my home wifi network when i have hardcoded the credential in wifi settins?