I've bought iPhone 4s and use it with China Mobile sim here in China.
I'm experiencing a very annoying issue that makes my new iPhone 4s almost unusable: every now and then (pretty often actually even several times a minute sometime) I keep on receiving a "welcome message" from China mobile on a black screen with "cancel" and "accept" buttons in the bottom (see picture)
The message says "Dear customer: thanks for chosing China Mobile, China Mobile wishes you a great success" (or something like that, I got it translated by a colleague).
The annoying part is that this message keeps on popping up continuosly and it actually interferes with the use of the telephone (e.g. if I'm using Siri and the message pops up, I have to start all over again and so on).
Strangely enough the message pops up even in airplane mode, with cellular data deactivated, with or without WiFi etc.
I called China Mobile and they told me to call Apple, I called Apple and they told me to call China Mobile.... Nobody seems being able to support.
I've been using iPhone 4 with the same SIM card until a few days ago and never experienced such a problem!
I must also say that the battery life of my brand new iPhone 4s is very short and I think it's because it keeps on trying 3G data connection (not available from China Mobile) that unfortunately cannot be deactivated anymore in iPhone 4s with iOS 5 (the option is still there with iPhone 4 with iOS 5). Network reception is also disappointing I presume for the same reason: if I could deactivate the 3G data (while keeping 2G data active) it would probably not happen.
I hope someone out there is able to help me.
Obviously I've been trying all sorts of resets (iPhone restart and reset, data connection reset etc.).
Stefano Bizzarri, Shanghai.