Arc has been inaccurate since the last big update

[fra]

Around a month ago (roughly the time the ‘unconfirmed’ and ‘uncertain’ places were introduced), Arc started to become inaccurate for me, as follows:

• I’ve been using Arc for a year-and-a-half, and it previously tracked the routes I walk at the same distance each time. But now some routes have sometimes (but not always) become longer: a 1.7km walk is often up to 2.3km, for example.
  

  
  
  
  

• Walking is now often logged as ‘stationary’ and I have to manually mark all those ‘stationary’ segments (mostly 1 second long) as ‘walking’ to fix it.
  

  

• I sometimes get doubled up logs (i.e. two logs of the same location, but with slightly different durations):
  
  

I have both Arc and Arc Mini on my phone (if that makes a difference). I’m running iOS17.7.2 on iPhone SE (2020).

Is anyone else experiencing similar issues?

[fra]

And another issue, possibly related: Arc sometimes thinks I’m cutting across fields and houses when I’m not. (The grey line curving at the bottom of the image is where I actually walked on this trip.)

[matt]

@fra

I have both Arc and Arc Mini on my phone (if that makes a difference).

Definitely makes a difference! A few people now have reported problems that have been related to Arc Mini.

Arc Mini is unofficially deprecated now (I just haven’t made an announcement about it yet). And everyone is recommended to use Arc Recorder instead.

I don’t yet know why Arc Mini is creating problems. But at this stage it’s not going to get fixed - it’s instead going to get removed from the App Store, as a no longer necessary app. The fallback recording / data gap protection job is now done better by Arc Recorder, and Arc Mini’s UI has never been loved by anyone. So it doesn’t serve any useful purpose anymore.

Once you delete/uninstall Arc Mini I’m fairly sure the problems you’re having will go away! Though if not, certainly do let me know.

[fra]

Thanks, Matt.

I’ve deleted Arc Mini and installed Arc Recorder instead. Will let you know how things go.

Arc Recorder seems to have the blue band at the top of the screen permanently on:

Without Arc Recorder, there is no blue band:

Is this normal?

(Do I need Arc Recorder, or is it fine just to use Arc on its own?)

[matt]

Yes unfortunately that blue bar is normal. That’s Apple’s choice, and as you’ll probably see in some other discussions, it’s incredibly unpopular with everyone on the forum including me!

@fra

(Do I need Arc Recorder, or is it fine just to use Arc on its own?)

If you have only Arc Timeline app running there’s risk of data gaps. Arc Recorder acts as a fallback, to take over recording if Arc Timeline is terminated by iOS, avoiding data gaps in your timelines.

Also there’s a toggle in the Privacy Settings in Arc’s Settings tab to turn on the blue bar for Arc Timeline too. Which is unfortunately almost a necessity now, due to Apple’s decisions around location recording. If it’s not turned on, there’s higher risk of the app being terminated, thus higher risk of data gaps. Also without the blue bar on Arc has to use less energy efficient recording settings, thus using up more battery. It’s a shit situation Apple have put us in.