Q: "Phone" app freeze on iOS 10

Having same issue with my iPhone 6s Plus. Phone app is just freezing with 10.0.2.

After i've disconnected Outlook, Gmail and Exchange as described problem was suddenly solved.

There are at least 5 other posts reporting this same problem:

https://discussions.apple.com/thread/7671180

https://discussions.apple.com/thread/7666112

https://discussions.apple.com/thread/7671366

https://discussions.apple.com/thread/7681132

https://discussions.apple.com/thread/7679372

"Phone" App keeps crashing under iOS10, reboot, reset do not help.

Apple, please tell me you are gonna fix it in 10.0.3!!!

Man, you saved my day! Thanks you!

I have been bugged by this for the entire last week!

Shame on Apple for releasing such buggy software!!!

I've been struggling with this problem since upgrading to iOS 10, I also updated to iOS 10.0.2 and still had the problem.  My iPhone 6s would hang/freeze when receiving calls.  Sometimes the phone would come back after 20-30 seconds, other times it would reboot completely.  Whenever I tested this at my office during the day it would fail.

Apple Support had me try and restore my phone through iTunes without restoring my data.  I did this at home in the evening and the phone seemed to then work OK.  Apple Support think it's something in my data causing the issue.  However I restored my phone and restored my data and the phone worked OK at home.

The next day at the office the phone failed again and failed 9 out 10 times I tried it.  I tried removing my Exchange contacts and that didn't make a difference.

I then realised the difference between the office and my house is the mobile network.  At home I have a 3G signal, at work I have a 4G signal.  I found that if I go to Settings > Mobile Data > Mobile Data Options > Enable 4G and change the setting from Voice & Data to Data Only my phone works all the time!! (I hope I'm not tempting fate saying that!)

It seems that iOS 10 has a problem with voice calls over a 4G network.  I'm with EE in the United Kingdom. 

As a extra aside, in Settings > Contacts I disabled Contacts Found in Apps as I thought that might affect it.  I'm not sure that it does as with this off and 4G Voice on the phone fails.  Might be worth experimenting for others though.

So the 4G setting seems to have fixed the issue on my phone.   If anyone else finds disabling 4G fixes there phone please post it here!

MY iPhone 6s Plus has developed a new issue as well as locking up more frequently. It locks up when doing a lot of web browsing. Or even looking at my photos. The app freezes and I can't get out of it or change apps. Won't even let me kill the app. But now my camera has messed up. It doesn't show anything but a black screen and if inswitch between modes like video to still to slow mo. It shows live view then goes blank. If I reset the phone it works fine for a while.

PLease fix fix this this is becoming more and more inconvienient.

I had the same problem - phone function was locking up occasionally.  I was at the Apple Store Friday about a problem with my iPad.  i mentioned the phone problem to the technician and he had me do a phone reset and this fixed all the problems.  The only downside is that any settings that were created, such as ringtones, wallpaper, screen font, all go to default and have to be respecified. 

The process is:   Settings, General, scroll to bottom, Reset, Reset All Settings.

Reset makes no difference to me.

I'd reported this as a bug a couple of days ago along with a log file.  The report has now been closed as duplicate of another report. So at least it's known about.

I have an iPhone 5C.  Phone call is biggest problem.  It will stop in the middle of a conversation.  Sometimes I can still hear the person but they can't hear me.  Only solution is to call back and start the conversation somewhere in the middle.  Today it happened 4 times on the same call over a 15 minute conversation.  The phone sometimes looks to be normal but my voice cannot be heard.  Other times my phone goes into what appears to be shutting down  You know the little spinner in the middle of the screen.  But it doesn't shutdown, it will just require me to sign back in with the Home Button.  The dropped call used to happen more frequently than I like with the 9.3 iOS, but I chalked that up to bad service/dropped call.  But now it is much more frequent with iOS 10.0.2 than before.  And I'm still calling form the same location my home office.  

I have iPhone 6s and after iOS 10 update, the contacts and phone apps freeze regularly. The screen becomes unresponsive. The app crashes or I need to shut down the  app. It has become so annoying.

Did you do a "Reset All Settings"?   This was a complete fix for me.  (Except for having to reaccomplish my wallpaper, ringtone and such customizations I'd added).

Confirmed that the issue is resolved by removing Contacts sync from other email accounts and leaving only iCloud account contacts.

I removed both from Exchange and Gmail but it is possible that one or the other is at fault.

I sync the accounts on my iMac inctead

I had the same issue with iOS 10.0.2 on an iPhone 6s. It began with the latest 10.0.2 update, not with the initial upgrade from iOS 9 to iOS 10 (either that or I simply didn't notice it until 10.0.2).

Symptoms:

After the Phone App is inactive for more than 1 hour, launching the Phone App will cause it to hang and eventually crash (just closes) after a varying amount of time in "hung" state. During the time the Phone App is hung, no touches register within the App. The home button still functions and app switching works as expected, but until the Phone App is terminated or times out, it remains unresponsive.

Research:

I've spend some time researching this issue and after reading a bunch of comments on this thread even considered a full factory reset. Instead, however, I decided to do the work of an iterative approach of testing to see if the issue is actually related to the Contacts App than the Phone App itself. To do this, I went into Settings->Mail, Settings->Facebook, Settings-iCloud and for each Synced account turned off Contacts Sync and then opted to delete the contacts form the phone. I then open the Contacts App and ensure there are no contacts shown. Essentially now the iPhone's Phone App history just showed numbers without any names. Same goes for the iMessage App. I then re-tested to see if the issue with the Phone App freezing would recur and it did not.

I waited 3 days and rebooted my phone several times to ensure that the Phone App freezing issue would not return and with all contact sync accounts removed and the Contacts App completely empty, the Phone App did not exhibit freezing a single time over the 3 day period.

I then slowly re-enabled each synced contacts account one account at a time.

Resolution:

After re-enabling contact sync for each account one at a time, I found that after re-adding contact sync on an outlook.com mail account, the issue with my Phone App freezing returned. Therefore I am tentatively concluding that either the issue is related to Outlook.com account Contacts syncing or more specifically a perhaps malformed contact part of my Outlook.com account. I am currently testing my iPhone with contact Sync for the outlook.com account disabled and have not seen the Phone App freezing issue.

Hope it helps,

David V.

TLDR: Try disabling just contact sync on each of your synced accounts one at a time and re-enable one at a time slowly to find the account that may be causing the issue.

Congratulation!

You must be a good engineer!

I Reset All Settings about 3 days ago and everything has been fine since.  This does not delete data it just got rid of wifi passwords, ring tones, etc.  We will see what happens over this week, but it looks promising.

Sorry to inform you David V but Outlook.com is not the issue here.

I removed all contacts sync accounts and issue disappeared.

Added only iCloud and issue not there.

Added only GMail and issue not there.

Added iCloud and GMail issue came back.

I think it has to do with multiple contact account syncing.

Especially true if you have contacts that you merged to have cards on more than one account. For example all my contacts are merged to have two cards, one on iCloud and one on GMail.

What I believe happens is that the latest app tries to check for changes on both contacts accounts causing it mess up. Especially if you have modified a contact locally on the phone (ie contact's name).

In fact, if you run Contacts.app on a Mac and you start managing contacts with multiple cards you will eventually see it slow down considerably as it tries (badly) to synchronize all linked accounts. I have even seen it crash.

Some theories anyway.