Hi, I recently installed V4 (backstory in case anyone’s interested), and on first launch it detected my V3 data (“Existing Data Found”) and started importing it. This took a while (my timeline goes back to 2019), but I believe it completed successfully… or did it? The app is working great - I love the new, snappier interface! But when I try to access a previous date (any date before today), I just get an empty timeline, sometimes with some unrelated photos displayed too.
Did something go wrong with the migration? Or does V4 simply take a while to process all the imported data (something I have seen @matt allude to elsewhere)? It’s been over 24 hours now and the situation hasn’t changed. Right now I’m running V3 and V4 concurrently, but I don’t think that’s going to be very good for my battery life
Any ideas what might have gone wrong here? Anything you recommend that I check, or do?
Hi HuiWaa — this looks like the migration didn’t complete cleanly, even though the app now considers it finished (which is why it isn’t offering to resume). The good news: nothing’s lost — your full history is still in your original app, and since you’re running both, there’s no risk to your data here.
The reliable fix is a fresh import: delete Arc V4, reinstall it, and let it import again from scratch. Your original app stays untouched, so nothing’s at stake.
The thing that matters most the second time is letting it run completely uninterrupted — an interruption partway through is the most likely reason a migration ends up in this state:
Keep the phone plugged in to power
Keep Arc in the foreground while it runs — don’t switch to other apps
A quick glance that there’s comfortable free space on the phone (very unlikely to be the issue on a recent device, but it’s a known one)
With your timeline going back to 2019 it’ll take a while, so give it room to finish. I’ll be straight with you about expectations: if the first run was tripped up by one of those external factors, a careful second attempt should come out clean. If it wasn’t, there’s a chance it lands the same way — and if so, we’ll dig in properly from there.
One optional thing that would genuinely help us, before you delete anything: a screenshot of one of those past days that’s showing photos. Once you re-import, the current state is gone, and there’s a detail in it we’d like to look at. Totally fine to skip it and just get straight to the fix if you’d rather.
Oh on this one, no need to worry! Neither app consumes considerable battery life in the background. And certainly not on a new phone. You’re all good to leave both running for as long as you like. I still have both running all the time on my 15 Pro.
Thank you @claude and @matt. I will try running the import again - before I do, does that mean I will lose the few days I’ve recorded (without a hitch) on V4? Or can I use “Backup & Restore” to recover them after I’ve reinstalled?
As for the failure modes, here are a couple of screenshots - the first one shows an imported day that should contain a few tracks showing where I drove that day (as it does in Arc V3). Instead, it shows no tracks and some random photos from my library that turn out to be from mid-2021!
Exiting the app and relaunching it usually solves this. Any ideas what might be causing this? Could it be a related problem?
Well, I hope this is useful to you. Once again I appreciate your help, and once you’ve confirmed I can back up and restore my V4 days, I’ll go right ahead and reinstall.
Thanks @HuiWaa — first, the bit that matters before you touch anything:
You won’t lose your recent days. You’ve been running Arc 3 alongside Arc 4, so Arc 3 recorded those same days too — and a fresh install re-imports everything from Arc 3, so they come back with the rest of your history. You don’t need Backup & Restore here; restoring a backup would actually just reinstate the half-migrated state you’re clearing. What keeps you safe is simply leaving Arc 3 installed until the new import looks complete — that’s your net. (The only thing that wouldn’t carry is any cleanup you did only in Arc 4 on those few days; the recordings themselves are safe in Arc 3.)
So you’re clear to go ahead whenever — no need to wait on us. Just give the re-import that uninterrupted run we talked about (plugged in, Arc 4 in the foreground, room to finish).
On the two screenshots:
The past-day display problems are part of the same incomplete migration — a clean re-import should clear them. If any day still looks off afterwards, grab a screenshot and we’ll dig in.
The second one (tracks not loading, map stuck until you relaunch) is a separate issue we’re already tracking, as BIG-599 — unrelated to the migration. Relaunching is the right workaround for now.
