Apple Maps quits regularly and unpredictably.

@MNEd are you certain of the route mode you were using during your incidents? I assume you asked the Map to route for cycling - but just want to make sure you hadn't selected another type of travel mode.

I have been able to reproduce the crash scenario I'm seeing on three separate iPhone12's. The routes have always been in walking mode. And the phones have always been in my pocket when they crash. I noticed that @MNEd also mentioned having to pull the phone out when it stopped working - presumably it was in a pocket or backpack?

I don't have enough data yet to conclude that pocketing the phone is a necessity to induce this crash but it's something to consider. Another interesting similarity between the crashes I've detected is the crash logs all report the same base64 values for the instructionByteStream at time of crash:

"instructionByteStream" : {"beforePC":"fyMD1f17v6n9AwCR893\/l78DAJH9e8Go\/w9f1sADX9YQKYDSARAA1A==","atPC":"AwEAVH8jA9X9e7+p\/QMAkejd\/5e\/AwCR\/XvBqP8PX9bAA1\/WfyMD1Q=="},

This suggests that this is almost certainly a software bug in Maps. Unfortunately, it's not yet clear what the trigger is for this crash as I am unable to reproduce it reliably yet. There are many instances when Maps does not crash on a walking route with device in my pocket. Will continue to test in hopes I can find a repeatable trigger. Currently A-B testing Maps "Enhanced" walking navigation setting which reportedly uses the phones camera and other sensors to improve accuracy (this setting is not available for cycling mode so it could be a red herring).

If any Apple representatives monitor these forums, I am willing to share my crash logs with you.

This issue might be corrected by resetting location and privacy settings found by going to Settings->General->Transfer or Rest iPhone->Reset->Reset Location & Privacy.

Limited initial testing after performing this operation has so far seen no recurrence of the issue.

I spoke too soon. Just happened again this evening. Maps app is definitely crashing as there is a log generated:

...

"bug_type" : "309"

...

"basebandVersion" : "4.20.05",

"exception" : {"codes":"0x0000000000000000, 0x0000000000000000","rawCodes":[0,0],"type":"EXC_CRASH","signal":"SIGABRT"},

"termination" : {"flags":0,"code":6,"namespace":"SIGNAL","indicator":"Abort trap: 6","byProc":"Maps","byPid":310},

"asi" : {"libsystem_c.dylib":["abort() called"]},

"faultingThread" : 8,

...

So something is causing our devices to crash. My iPhone has almost no 3rd party apps installed so I think this is not related to 3rd party applications. I believe all iPhone 12 generations have the same modem as well. I will have to wipe the phone and go totally stock to see if the problem remains.

I'm seeing similar behavior with an iPhone 12 however not with an iPhone 12 mini while routed and used simultaneously on the same route. Does not appear to be related to cellular signal as I've tested while using hot spot of alternate phone that continued to route path. All testing done while on a walking path. In my case, the Maps just quits as though it crashed. When I relaunch Maps it continues the route from where it left off - I do not have to re-route to the original location.

I reviewed that other post and that user seems to be reporting a slightly different issue - as I interpret that post, it sounds like their screen isn't staying illuminated the entire time that a route is in progress rather than quitting altogether.

I have also run Apple's diagnostics suite on this device found and it was found to have no faults.

Reading through more of the log suggests that this crash was due to “Address size fault”.