Arc crashes all the time

[daanjj]

I am using Arc since quite a few years, and with pleasure. However, since a couple of weeks (could be months actually), Arc keeps on getting stopped or just crashes. I have put in quite some time to fix the last weeks, which is a time-consuming challenge as different segments have been put together erronuously and there are a lot of time gaps.

I am always on the latest iOS (18.3.2 at the moment) and Arc (3.17.1) versions. And have installed the Arc Recorder (v1.01) two weeks ago. Running on an iPhone 16 Pro. Have never installed Arc Mini.

[matt]

Hi @daanjj!

There’s no known issues causing the apps to be frequently terminated at the moment. Typically Arc Timeline should stay alive for days at a time, and Arc Recorder even weeks at a time (assuming the phone isn’t restarted for iOS updates etc).

Are you meaning crashes while the app is in the background recording, thus causing data gaps? Or are the crashes when the app is in the foreground and you’re browsing around in it / editing data / etc?

[daanjj]

Arc continues to crash multiple times per day. Like today, it crashed at least 3 times. Everytime when I notice, I restart. It does a lot of ‘processing timeline’ (after a crash) but also crashes when it is done with ‘processing timeline’. Because of this, on almost every day parts of where I drove/ran/walked are missing. It is extremely annoying and as said before, it is quite new behavior. In the last years, I almost never had to restart Arc and my travel logs were almost always perfect.

Because of all the crashes, I spent quite some time cleaning up previous days. So I would love to get some help in finding the culprit and resolving these crashes!

[matt]

Can you identify a specific action and place where it happens? Like, what action had you just taken in the app, and where in the app is it when it crashes?

To debug it and determine whether it’s a known case or something different it will help a lot to have those specific details. Thanks.

Oh also, if you’re getting data gaps, make sure to install Arc Recorder app, so that recording can still continue even if Arc Timeline app crashes.

[daanjj]

Hi Matt,

the app crashes 2-4 times per day. Today, it crashed twice in the morning while still at home. It also crashed once during the day, so the recording of a 6k walk was mixed up with a car ride I did after the run back home. It also just crashed while I was editing a ‘brief stop’ consisting of one ‘walk’ segment and one stationary segment with bogus data. When I changed the latter into ‘walk’ (as it was during that 6k walk) the app crashed.

Other than sometimes when cleaning up, there is no specific action that I am aware of that causes these crashes. The timeline is ‘ready’ with processing. I try to solve ‘uncertain items’ regularly since the problems started.

Arc Recorder is also active. And both apps are allowed to record in the background.

[matt]

Ok so sounds like the crashes are happening when you’re doing editing?

Do you often use the “Timeline Cleanup” view? That being the one that you get to by tapping the banner at the top of timeline view, for “1 uncertain item” etc.

It will be super helpful to identify exactly the action and location in the app you were at when the crashes happen. If it’s not when you’re doing editing from the Timeline Cleanup view then it’s something I’m not aware of, and I need to investigate.

If it is from the Timeline Cleanup view, then what I can say is that Arc Editor app is coming soon, and solves all those problems. If it’s not from the cleanup view then it might be something different that I can investigate and potentially fix before Arc Editor arrives.

[daanjj]

Arc typically crashes while running in the background (2-3 times per day) and also sometimes when I am using the app to edit the timeline. The only reason I now more often edit the timelline is because of these background crashes. I understand that when a background app is using too much resources, iOS might kill it. So since the crashes started happening frequently, I do quite some timeline editing. Unfortunately I don’t see any difference, it keeps on crashing.

Today (while not using Arc) I already had to restart the app twice. And while typing this and editing the timeline, it just crashed a 3rd time…

If you can provide me with a debug version, hapy to further explore what is causing this crashy behavior!

[matt]

Ah ok, background! Well that’s a very different story then. In that case it’s likely not “crashes” but “terminations”. Slightly different terminology, so I was looking for the wrong things before.

Ok so in that case we need to figure out why iOS is terminating the app so often. Maybe once every day or two would be normal, but more than once a day isn’t normal, and for sure something we can try to hunt down!

Ok so above you said that both apps have background permissions. But just to tick the box we’d better double check that both have “Always” location permission, also “Precise Location” is enabled, and “Background App Refresh” is enabled for both apps. I’m guessing those are all already correct, but have to check just to be sure.

Next up… well, the next box to tick is just to make sure you’re definitely not swiping the apps closed from the iOS app switcher. If you’ve been using the apps successfully for a while and this has only started recently I’m guessing that’s also very unlikely. But yeah, have to tick the box, just to be sure we’re checking every possibility. Swiping the apps closed will of course cause them to be terminated

Now on to stuff in Arc itself. Do you have Arc’s optional daily/monthly auto exports turned on? If so, we should experiment with turning those off. Those are very energy hungry, and high risk for making iOS angry. Which can then result in iOS terminating the app due to energy use.

If those are already off, then… that’s all the obvious and easy stuff eliminated, and things get much more tricky to debug! So now we need to switch in to detective mode and start looking for indirect clues. Changes in usage patterns, new large apps being used, recording more videos, that sort of thing.

Using the Camera app to record videos is high risk for causing iOS to kill off almost all other apps. It can depend a lot on which phone model it is (more or less RAM, so more or less likely for iOS to kill off other apps to make room for video in memory).

Games are another potential culprit. Large / graphics intensive games can cause iOS to kill off all other apps, similar to with the Camera app.

Beyond that, yeah, we have to look for subtle clues like … well … anything we can think of really. What’s changed between when it was all working fine and now, with it not working fine?

[daanjj]

Sorry for the confusion. I indeed experience both crashes and terminations, with the terminations being very frequent (1-3 times per day, every day). Last one was somewhere during the night, even though I spent quite some time yesterday to clean the last days, so there was no processing ongoing when I went to bed.

I also notice frequently that Arc just missed part of my travels, giving odd straight lines between 2 points instead of following the road I traveled on. I am not sure this is directly connected to the terminations; it might also happen while Arc continues to run in the background. (My travel pattern yesterday showed some of those straight lines but as fas as I remember, Arc wasn’t terminated during my travels.)

Then the checkboxes.

• Arc Timeline has background permissions turned on, however I don’t see Arc Recorder in the list of apps that asked for background permission? Strange because I am pretty convinced it was there before.
• Both the “Always” location permission and the “Precise Location” are enabled for the two apps.
• I almost never swipe apps closed, and I definitely never close the Arc apps
• I have both the automatic daily and monthly GPX file exports enabled; I have switched both as I write this reply. (I left the iCloud Drive backups switched on btw.)
• As for the other stuff: I occasionally use the camera app but mostly for photos and never for movie clips longer than 2 minutes. I never play games on my iPhone or (as far as I know) use other resource-intensive apps
• Some other facts: Arc is the highest battery user on my iPhone 16 Pro, with 10% usage in the last 24 hours and 16% usage in the last 10 days. My phone typically needs a recharge in the evening despite being just over 6 months old.
• I always update to the latest iOS version within 24 hours of it becoming available, running iOS 18.4.1 since yesterday evening

Hope this update helps in finding the root cause!

[matt]

Thanks for all that info @daanjj!

@daanjj

I have both the automatic daily and monthly GPX file exports enabled; I have switched both as I write this reply. (I left the iCloud Drive backups switched on btw.)

Ok so this is probably the most telling. Definitely leave the iCloud Drive backups turned on! But yeah, turning off the monthly auto exports will definitely help. For some reason those ones are especially problematic, making iOS particularly angry. The daily auto exports also, but less so. Definitely turning off the monthly auto exports should help a lot.

Aside: I’m rebuilding all that auto export / backups stuff in the new Arc Editor app. It’s already partially rebuilt, and works much faster and more reliably now. I really can’t wait to get Arc Editor into public beta!

@daanjj

Some other facts: Arc is the highest battery user on my iPhone 16 Pro, with 10% usage in the last 24 hours and 16% usage in the last 10 days. My phone typically needs a recharge in the evening despite being just over 6 months old.

Yeah that’s not good. It definitely shouldn’t be that bad! For context: I use Arc Editor and Arc Timeline repeatedly throughout the day, because I’m working on them and testing them almost every waking hour of the day. But for me Arc Timeline is 5th down the 10 day battery list and 7th down the 24 hour battery list (both at 4%).

Arc Editor is showing up at the top of the lists for me, but that’s unavoidable. I’m literally working on it in the foreground for 3-6 hours a day at the moment. But for Arc Timeline I’m still testing that throughout the day, comparing results to Arc Editor, etc, and yeah that’s 5-7th down the list and only 4% battery.

So yours showing top of the list and 10% is … not right! And more concerning is your 16 Pro needing recharging in the evening. My 15 Pro … well ok it’s not really comparable actually, because it’s plugged in to USB power for 3-6 hours a day while I’m doing development work on it, so… yeah, can’t compare in that case.

But for the rest, yeah… that top of the list and 10% is a concern. The question is… why is it like that…

To which I don’t have a good answer, unfortunately. It’s hard to imagine you’re getting more screen time with the app than I do. Or maybe you are getting more screen time. For me Arc Timeline is showing 6 minutes over the past 24 hours. Which can’t be right at all - that sounds physically impossible, given I was doing debug work on it yesterday afternoon. I don’t actually have high trust in the Settings Battery view. It often says things that seem quite counter to observed reality.

It’s showing 1 hr 35 mins screen time over the past 10 days, which also sounds quite low. That comes to about 10 mins a day, which again sounds suspiciously low given the amount of debug testing I do. Hmm.

Anyway, yeah that’s the next thing I’d check. In the Settings Battery view, how much screen time is it showing for Arc Timeline over the past 24 hours and 10 days? It’s the screen time that chews up almost all the energy use. Like, 5 minutes of screen time could potentially chew up just as much battery as 5 hours of background recording.

[matt]

For context, here’s screenshots of what my 10 day Settings Battery view looks like.

This should represent very high usage, given that I’m working on both Arc Timeline and Arc Editor for part of each day, and testing both of them throughout each day. The screen time numbers for both of them look suspiciously low to me. But… no way to validate whether it’s giving correct data or not.

[daanjj]

I switched the daily and monthly exports off. As a result, Arc is terminated less frequently than before, from 2-3 times a day to once a day. So still not where it should be.

[matt]

Once a day sounds about right, unfortunately. Though if it’s at a bad time then it’s problematic. But if all is going as well as can be expected then it’ll typically be some time while you’re at home, while plugged in to power, and iOS has decided to kill off some apps while the phone is in standby / not being used.

If it’s at a bad time, then yeah, still more debugging to do to hopefully improve the situation more. But one termination per day is pretty typical. Though Arc Recorder can often see multi day sessions with no terminations (I’ve seen it occasionally get left alone for over a week!)