after a recent long (~1h30m) drive I saw Arc only recorded the start and the end and then drew a straight line through it. I assume Arc was killed shortly after the start of the trip. Arc Recorder was also running the full trip and not killed. I assumed the 2 would negotiate the difference and fill in the blanks but that never happened. Is there a way I can help here?
Many thanks,
Jan.
Ugh. Yeah sounds like the communication between the two broke down somehow. Which is not a known problem to me at the moment.
There was such a situation a while back, where there was a logic fail in the communication between different versions or the apps (newer version assuming older version was doing things it wasn’t). But that one’s been fixed, so this will be something else.
My hunch is it could be a situation where Arc Recorder had actually been suspended by iOS. Like, the apps are meant to be always “alive” in the background, albeit doing nothing while in standby. But iOS can still decide to fully suspend the apps if it wants to. They’re requesting not to be, and following all the rules to not be suspended, but iOS is the boss and ultimately it does what it wants at the end of the day.
Or another possible scenario is that iOS wasn’t delivering correct/new location data to Arc Recorder, so Recorder thought you hadn’t gone anywhere and was just happily sitting there, oblivious to any moment. That… can happen too 
Though thankfully only very rarely. But yeah, can happen.
Unfortunately both of those situations are out of our control. It’s just iOS doing its thing how it wants, not how we want, for its own private reasons.
But I don’t want to say “that’s just life” and leave it. There’s got to be … something we can do. Hmm. Ugh. I’m drawing a blank. All of the reasons why this might be happening (unless there really is another communication breakdown bug in the apps that I’m not aware of) are reasons that won’t show themselves to us. We simply won’t know that either of the apps … oh wait, well, there’s the “Current Item” widget.
Ok so the Current Item widget will show you little green/red dots for each app, to indicate whether it’s still alive or not. That will reveal the “iOS suspended it” problem, when that happens. If the app has been suspended it’ll no longer be communicating, so the dot will turn red within a couple of minutes. This little thing:
That’s showing that both Arc Timeline and Arc Recorder are alive and well right now. (Well ok, 10 minutes ago. Sigh. iOS hasn’t updated the widget as timely as I’d like it to. Another thing out of our control). But yeah, two green dots = all is well.
Though that doesn’t catch the case of iOS deciding to stop delivering new/correct location data to the app. That one must surely be classed as an iOS bug. But it’s the kind of thing that it’s fruitless to report to Apple, because they’ll require a strict reproduction case, with test code etc. It’s the kind of thing that happens randomly, one day in a month, for no obvious reason. No way they’d take any interest in any report of it.
But at least the widget helps for the first case!