I have 2 iphones on one itunes account. I just upgraded both to ios 8 and now the messages i receive come through to both phones when they used to be seperated. What is going on here?

Go to Settings/Messages/Send and Receive and uncheck the email addresses and phone numbers from each phone that you don't want THAT iPhone to receive the messages. Apparently when doing the upgrade to iOS 8, the default is to return to all numbers/emails associated with an Apple ID to be selected again. (I had to do the same thing on two iPhone 5 and two iPad Minis.)

Are phone calls also ringing both phones or just messages?

Same here. I have two phones XXX-XXX-X703 and XXX-XXX-X283. After iOS 8 installed both would ring when X283 would get a phone call. Only way it stopped was to log X703 off of the Apple ID (using same). However, when you log off you can't see that phone on "Find iPhone".

Swandy. Thanks but messages are fine as I had already edited the numbers. Phone calls only. I did see an earlier post to turn off Iphone cellular calls within Settings --Facetime.

Check the Facetime settings. I don't have my phones with me! I read earlier that turning off Iphone Cellular calls within settings and Facetime may resolve the issue.

I noticed the same problem after upgrading a few iPhones to IOS 8, all use the same Apple ID. However, I now notice when I go into Message and instead of selecting a person from my contact list, I start typing their name which brings up a list of people, some of which are not in my contact list and are on one of the other iPhones. There's a circle/exclamation point next to the name which I click on, and one of the options is to "Remove from Recent". How did these names get from one phone to another and how do I remove all "recents"? They do not appear in my contact list. Anyone see this?

I have the same exact problem as KCiPhone5s. One iTunes account, 2 iPhones - my wife upgraded to IOS 8.1 today (I did earlier this week). We don't see each others contacts in phone or email contacts. But in messages we can both see the others contacts when starting to type a name.

Anyone else having the same issue?

This has happened more recently to me and its because of a new feature in IOS9 called "Calls on other devices"

After I recently upgraded from ios8 both my and my wifes phone would ring on an incoming call. The only difference was that on her phone it said "from iphone'.

I checked this forum and noticed all the suggestions but they didn't seem to work. Then i had a poke around in the settings myself under the phone menu i found "Calls from other devices". This was activated on both phones and was activated by default when the upgrade from ios9 happened. It had listed my wifes phone and my phone respectively on each handset and also included the ipad for good measure. I imagine this new setting was incorporated to pair with the iWatch.

I switched this off and the problem was fixed.

No. It's actually a feature called "Continuity". The actual solution is not to share an iCloud account with anyone else. Each person should have their own account for iCloud.

does anyone know if this costs anything with both phones ringing? I have a work mobile and personal mobile so it's great for me. Just need to know if it's using data or if there are any costs?