I installed Arc Timeline and Arc Recorder. Is it right on Arc Recorder, I have to „start recording“? Arc Recorder is only for backup? And Arc Mini I don‘t need, when I have the both other installed?
Yesterday, my IPhone had only 10% battery. Is it right, that Arc timeline and Arc recorder will not record automatically anymore, when the battery is so low?
The “Start recording” / “Stop recording” buttons in each app control recording for both apps. If you turn it off in one, that turns it off in both. And likewise, turning recording on in one app turns it on in both.
Yep! When both apps are alive, one will be doing the recording and the other will be in “standby mode”, using effectively no energy / no battery consumption. Then if the actively recording app gets terminated, the other app will notice that it’s gone, and within a couple of minutes it will take over as the active recorder.
This process helps to almost completely eliminate data gaps in the recorded timeline. If there’s only one app recording, and it’s terminated, then there will be a data gap. But with two apps, one waiting in standby, the energy use / battery use is roughly the same as with only one app, but you get protection from data gaps.
They’ll both continue doing their jobs! When the battery level is below 20%, Arc Timeline app will record less detailed data (although not so much that you’d notice any difference in the timelines), but it will continue recording regardless. And Arc Recorder will still be sitting in wait, in standby mode, ready to take over if needed.
Oh I forgot to reply to this question. Yep, you don’t need Arc Mini now that there’s Arc Recorder.
Arc Mini was an experimental app I built, to learn Apple’s new SwiftUI UI building framework when it first came out. At that time SwiftUI was very fresh and incomplete, and didn’t work particularly well. So mostly what I learnt was “SwiftUI isn’t ready” 
But now, five years later, SwiftUI is much more mature, and ready for use in large and complex apps. Arc Recorder is built in pure SwiftUI, as is the upcoming Arc Editor app.
Anyway, the short answer is: You don’t need Arc Mini. Arc Recorder does the same job of being there as a backup, to avoid data gaps. And no one really liked Arc Mini’s UI anyway - it was a bit awkward, partly due to various limitations in SwiftUI’s first few years of life.
Aside: Arc Timeline app is 80% old UIKit, and 20% SwiftUI, with newer features built in SwiftUI. But that mixture of old UIKit and new SwiftUI actually creates a range of mysterious and hard to fix bugs and problems. Which is why I’m keen to get Arc Editor built as a replacement for Arc Timeline, built 100% in SwiftUI. No more mixing of old and new, for less headaches, and less mysterious bugs!
Ok, thanks for your answer. I now have Arc Timeline and Arc Recorder installed and deinstalled Arc Mini. You wrote that you are building a new app Arc Editor. Is this new app included in your Arc Timeline Lifetime subsription? I mean no extra costs for this new app? When will you launch this version?
Another question, most of the time it tracks cycling. Even if I use the car or walking. Why it detect all the time cycling as default? Is it possible to set walking as default?
Yep! Arc Lifetime covers everything in the Arc family of apps.
As soon as I can!
I had to stop working on it for a bit, to do a bit of housekeeping work on Arc Timeline and Arc Recorder (there’s new releases of both, ready to go now). But I should be able to get back to Arc Editor next week, and my hope is that I can ship a minimal first version of it before the end of this month.
If the app doesn’t have much data yet, then it will be relying on the fallback “activity type model” for classification, which is really just a copy of my own personal model. I do a lot of cycling! So that’ll be why that model is sometimes more eager to see things as cycling.
But as your own data collects up, and your own personal activity type models get fleshed out, the app uses that fallback model less and less, and will instead classify things purely based on what it knows about your own data.
So to answer whether it’s possible to set walking as the default: That happens automatically. And each time you correct an item from cycling to walking, you teach the models that pattern, and cycling will fade away on its own.
Hi Matt, can you inform me, when the first version for Arc Editor is ready to download? Then it’s possible to use both apps (Arc Timeline and Arc Editor) at the same time?
Unfortunately I don’t have a good guess yet. Though I would hope before the end of this month, or early next month.
Yep! Technically it’s possible to run all of the Arc family apps at the same time (Arc Timeline, Arc Mini, Arc Recorder, and Arc Editor). Doing that provides extreme safety from data gaps. Though having more than two of the apps installed and running is a bit unnecessary and extra.
If I didn’t have to test them all myself, I’d only keep Arc Timeline and Arc Recorder installed and running. Though once Arc Editor is further along, I’ll probably keep those three apps installed, because for a while Arc Editor won’t have all of Arc Timeline’s features copied over yet.
I just installed the new Arc Recorder.
When it is running, blue Navigation arrow is always in Dynamic Island on iPhone 14 Pro.
That is a problem because it takrs space on screen and previous app is no longer showing.
So I cant’t just tap to jump to previous app.
Can you please hide the navigation marker in Dynamic Island because it’s already next to the clock. It’s only use is to tap and switch to Arc Recorder. Not very usefull.
Maybe you could make a setting to hide the blue navigation arrow.
@Jani, that’s something you have to ask Apple. That’s their decision, not ours.
I’m not sure what you mean: Dynamic Island or Previous app?
I accidentally found a setting in Arc main app (Privacy - Status Bar Location Indicator) that does just that: shows or hides blue location arrow. The description says that showing indicator lowers power consumption.
I would really like to have a choice to show or hide the indicator.
Is that too much work?
It’s not about “too much work”, it’s about Apple not wanting us to do it, and progressively making it difficult or impossible to do.
Arc Timeline app hides the indicator by using the very old Apple APIs that support doing so. Apple took away the option to hide the indicator in the new APIs they introduced in iOS 17 last year. And in iOS 18 this year, hiding the indicator appears to cause the app to be suspended in the background even when doing the less energy efficient recording style.
Basically Apple don’t want it done, in iOS 17 they introduced new APIs that didn’t support doing it, and in iOS 18 they appear to be punishing apps that do it.
It’s the end of the line for that feature. I’ll do a bit more testing in iOS 18 betas, but it looks like I’ll have to remove the option to do it completely.
If you don’t like this (and I don’t like it either!) then the only way to get it changed is to contact Apple and tell them you don’t like it. They don’t listen to me - I’m just one indie developer - but if enough iPhone owners say that it sucks and it should be changed, maybe eventually Apple will listen and do something about it.
Thank you for the explanation.