Q: iPhone 4s losing data connection multiple times/day

I agree!

Yesterday, 4 times I left a wifi-area and 3 times it did not fall back to Edge/3G, just no internet connection (and no Edge/3G icon). Switching to manuall carrier selection and selecting the automatically selected carrier manually still does the trick of getting Edge/3G back (you can swith Automatic back to ON and the connection remains)...

I really hope an update can fix this, soon.

Luckily my old iPhone4 (now used by my wife) still has no issues whatsoever with this...

I have the same problem, too! I don't understand why so many people have the same problem, and neither AT&T nor Apple do something or even say something. The most ironic thing is, when I was at the AT&T center in San Antonio last Wednesday, I had 3G receptions but no data at all. What a shame!

Im having the same problem but i have an iphone 4 and it started since i updated to ios 5.1

and i dont know what to do cause the 3G icon is their and i have full service with sprint but when i use the internet it wont connect cause i lost data connection or it tells me their is no data connection

I updated to 5.1 9B179 the day it came out (a week or so ago), so far I've not experienced the problem. 

Having the same problem with a new 4S. It appears to only be within a certain radius of where I work.  I have talked to att and apple multiple times with no luck. I guess I will start down the path of replacing the phone.

Do you have Wi-Fi Sync turned on in iTunes? I realized that after I turned that option off I no longer had data connection issues.

I saw this today and thought it sounded a lot like our problem on the iPhone:

http://www.electronista.com/articles/12/04/09/nokia.lumia.900.launch.marred.by.d ata.bug/

"Windows Phone losing all data connections if the cellular link is restarted at any point...

While not publicly confirmed by AT&T, a tip suggested that the IMEIs, or unique phone identifiers, weren't registering properly on the data network."

I rang Vodafone about this same issue and they mentioned the same or similar - that my sim card had not registered with the network. This results in it dropping its data connection. I think when you flip it to flight mode and back it forces the sim to reregister.

It must be linked to wifi somehow.. as when I switch off wifi as I leave my home network is keeps hold of its data connection...

switching to airplane mode and back doesn't do it for me.

The only way that always works is:

1. to go to Settings -> Carrier and then switch Automatic to OFF
2. wait till the list of carriers appears and then manually select from the list the carrier -> 3G/Edge magically re-appears.

It's then save to switch Automatic to ON again, data remains availble.

I agree with data loss being related to switching from wifi to cellular data. Never had it happen when a cellular data connection was present and not switching to wifi...

I hope this will be fixed in a future update. My wives 4 (not S) does not have this problem. Or would it be hardware related (different radio chip)?

A lot of us don't have that setting unfortunately. I wish I did because it would help prove to the genius bar folks what is happeneing. When you first go to the list is it missing the 3G/Edge option until you switch Automatic off?

When you go to carriers and you turn off automatic it does a search and will return all carriers. Orange/Vodafone etc...

You can then select the one you are on manually. At that point the 3g/Edge signal returns.

I too am having 4G internet connectivity problems with my new iPhone 4S.  I'm running the latest iOS 5.1 and I'm now on my second iPhone 4S.  I returned the first one to ATT after about a week. 

The problem I experience is that I lose 4G internet connection randomly (several bars are showing, the 4G symbol is present, and I can make phone calls).  The only way I have found to reconnect to the internet is to power the phone OFF then back on ON.

Toggling the Network->Cellular Data OFF/ON does not help, nor does switching Airplane Mode ON/OFF.  My previous iPhone 4, which my wife now haves, did not and still does not experience this problem.

Apple please find this problem.  I really believe you have a hardware/software interface issue that is peculiar to the iPhone 4S.  I'll give it a little while longer, but I'm getting very frustrated and very tempted to return the phone and go back to an iPhone 4.

I spoke with AT&T on numerous occasions, reset my 4s, restored, had apple check it at their store, replaced the phone, tried not installing apps, turning off features, and none of these things fixed the problem. I know Nokia had a similar issue with data on the Lumia 900, but at least they admitted it and took steps to make it right by the customer. So, I've jumped ship and now use a windows phone on LTE. At least it works. I hope everyone gets this issue fixed. C-ya!

My husband's 4s on iOS 5.1 has been having the same issue, the phone will show full signal bars and the "4G" symbol but he cannot receive any data.  The only fix we have found is turning the phone off and then back on.  I have the 4 on iOS 5.1 and have never experienced this issue.