All points and tracks lost since update to 4.28

I suspect that this is not possible and you will need a new database. I think that the time has come to abandon Locus Map classic

Hi Georg,

both apps use the same directory on Android 10 and older. Android 10 was released more than 5 years ago. We realize that the concept of sharing one directory for more apps had its advantages but we have to move on and comply with the latest Android developments.

Beginning with Locus Map 4.28, the track/route/point database is no longer compatible with Locus Map 3 Classic so if you want to use both apps, make sure both use a different main directory.

As for the Locus Map 3 Classic, it's entering its last year of maintenance and support. We are planning to terminate it completely in March 2026.

Hi Michal,

thank you for the explanation. Few words but deep content!

Just read the bold text to get the main message, and if interesed in one topic, also the normal formatted text of that topic.

1. Being surprised by lost data is not nice. So please, before you continue to roll out further update waves, please implement something making users aware of that breaking change introduced in v4.28 beforehand so that they can ASAP do a manual backup of v3 to be on the safe side (update to v4.28 does not trigger a v3 backup but may affact a v3 installation, and v3 auto backup seems broken so a manual backup shall be recommended), make their thoughts on how to continue with v3 and v4, and decide whether they want to update – and if yes, adapt their installation based on a short guide.
   I thought about how/what could actually be done. Some ideas:
   a) To avoid bothering users that can't be affected: Can you send a message in a way it reaches only users of v3? Sooner or later, most of them did or will install v4, thus all v3 users are potentially affected by the breaking change and shall learn about it.
   b) Can you configure Google Play Store automatic updates based on two versions? Aim would be that users having both v3 and v4 do not automatically get the update and run into the issue, but only after manual action.
   c) It seems you have already code running that detects v3 and v4 are using shared directory, e.g. v4.28 > settings > "file system manager" > "set the main directory" shows the dialog
   
   You could call that detection code at the very start of Locus v3 and v4, show an information about the breaking change, and ask whether app shall continue to start or it shall terminate. This avoids e.g. unintentional migration.
2. You write "sharing one directory for more apps had its advantages". For me, it's not past tense, but it's the only meaningful workaround to use Locus at all.
   v4 is just usable to experiment & play around with. 10+ crashes in 10 minutes (details in this topic) are unsuitable for tour planning, for navigation if you don't know the route anyway, even for simply looking at the map. So alone because of this issue, for "real usage", I simply need v3. But v3 did get none of the new developments like e.g. route planner "reverse route direction" feature, advanced search in points & tracks (RegEx etc), satellite online map,... If I want to use the results of Locus teams' work of last 4-5 years, I need v4.
   Hence, till 2 days ago, I used v3 and v4 in conjunction – even within one task like trip planning. Doing so with manually exporting & importing points & tracks back and forth is much too tedious and error prone, so it is simply required that both versions use the same points & tracks – I don't care whether it's the same DB file, or both apps have distinct DB files which are synced, or only one app has a DB file while the other app does API calls to fetch the data. You write
   "Beginning with Locus Map 4.28, the track/route/point database is no longer compatible with Locus Map 3 Classic". So I must now decide between "no v3 but only v4.28+ and a different map app for real use" and "v3 with v4.27". 1st option means I need to search for another map app now, 2nd option means the same but without time pressure: Because v4.27 won't receive any features & bugfixes and v3 does already get no features and as of 3/2026 also no maintainance, both will become "feature-wise old" and break piece by piece, e.g. when backend APIs change. I have little hope that in time, v4.28+ will become suitable for real usage, because for quite some while I did see no activity at all in the blocker tickets – which is a financially reasonable decision as it seems only a fraction of users have the issues. Unless activity is going on without being visible to users, only a co-incidence could make v4.28+ usable, e.g. that a library is updated/changed solving the blocker as a by-product and someone notices it (affected users can't any more as they need to stick with v4.27 thus do not try newer versions). That perspective makes me sad. Without glorfying the past (not everything was perfect), I really liked Locus and the team, and it feels like saying bye-bye to a person you enjoyed closely worked with for more than a decade 😥
3. How can I roll back to the state before v4.28 update did break both v3 and v4? So that I have v3 and v4.27 using shared directory, both versions can be used, both versions have all points & tracks and their according settings.
   I assume
   - start v4.28, My Library, search for empty term and sort by "Updated", export all points & tracks changed since update to v4.28
   - uninstall v4.28
   - download Locus 4.27 APK from https://drive.google.com/drive/folders/10nraA2tzZvoFW0lPtkOSAVTiAPso5Ovx (link from manual) and install it
   - start v4.27 and restore points & tracks from backup before update to v4.28
   Did I overlook something? Will that also "repair v3"?
4. As automatic updates in Play Store is every now and then changed from disbled to enabled, is there another way to ensure Locus v4 is never updated, or that My Library is never migrated? Maybe no update is done when an APK is installed from outside the play store. Maybe when v4 starts and shows release notes, the migration is not yet started, so the release notes are a sufficient warning for me that I shall kill the app and go back to an older version.
5. FYI, a display issue in new My Library which you may want to check whether it's a general issue in new My Library code, or only happening when v3 and v4.28+ are used with shared directory: Between creation of this ticket and your answer, I started several times v3 and v4, so v4.28 My Library contains several copies of the two folders Points and Tracks. In the root folder listing, all of the Points folders are shown to have 49 sub folders and 7843 points, but when diving into them, only the "first one" really has that much content, while the others have only 1 sub-folder with a hand ful of points – those few I created after v4.28 installation in v3 until I started v4.28 again. Similar for the Track folders. I would expect folders know their content and are not showing the content of some other folder.

I opened v3, restored points & tracks of backup from before update to v4.28, worked a little with v3 and everything looked OK, then wanted to try some stuff for other ticket in v4.28.1 so opened it. As expected, migration started, resulted in these 3 empty folders and v3's My Library was empty – I'd expect either v4 or v3 have data, not both empty. Restoring the auto backup from before migration in v3 worked, so no real data loss, but something is unreliable in the migration.

After I restored Library in v3 from backup, I used v3 and for sure not v4, switched to other apps, later came back to v3 and saw My Library was empty. In Android's task list, v4 was not shown, but in backup folder, a new auto back before migration existed – v4 must have started "halfway" but I have really no idea why. In this "incomplete" start, the migration was done better than before, i.e. after I manually started v4 completely, I saw the expected 2 folders only, and surprisingly, some points were visible (in contrast to this topic) – some but not all of the points where I expected it, and some points I definitely had hidden in v3. Moreover, some points were shown on map not with their defined icon, not folder icon, not default i-icon, but the icon tracks have (white zig-zag). Each day a different behavior of Locus v4.28.1...are you guys carnival fans and thus currently playing jokes on us users? 😉🤷‍♂

Hi Georg,

1. There are very few users using both LM4 and LMC, even fewer running Android 10 and even fewer with problems with crashes due to a glitch in an Android library. So, it makes you quite a unique user. Therefore, I'm afraid we won't introduce an overall procedure notifying all LM4 users about the necessity to back up their LMC databases before updating to 4.28+. Moreover, we have no influence on the auto-update switch on Google Play - it is solely controlled by the users. The "LMC detection code" works again for A10- users, of which there are only a few so I thing no more action will take place in this either.

2. "it's the only meaningful workaround to use Locus at all..."
- sharing one directory between two apps is no longer possible on Android11+. We can disagree with it but we have to adapt to it and take it as it is - we are not developers of Android OS. We are developing apps that have to comply with the latest Android OS design.

"v4 is just usable to experiment & play around with...."

- I'm sorry but this doesn't matter to the majority of LM4 users. Only a few users experience the crashes caused by the Android library and we can do nothing about it except wait for the library update. The Android OS developers have been informed long ago but so far, to no avail.

3. as I have written in another topic of yours, pre-migration LM4 backup can also be restored in LMC and vice versa

4. unfortunately, there is no possibility from our side to influence the app auto-update - ensure you have Locus Map excluded from auto-update in your Google Play.

5. please send a ZIP file containing LM4 Locus/data/database from after the migration and the pre-migration backup file that should be found in /Locus/backup:

We'll analyze both and try to find the solution. Also, please send your user ID from the LM4 (menu > about app > app info) - it may reveal some data about the crashes from the internal analytics.

Hi Michal, I'm back from my ski trip in Scandinavia for which I relied on Locus. Because of this relying on Locus, I became quite nervous when I discovered again and again new variants of how I lost data or saw inconsistent data after update to v4.28. Sorry if you got to feel that! 🙂

1. I see; there are several prerequisites thus only a small fraction of users is being affected and you can't easily notify only these users – then it's also from my point of view not worth bothering all users.

2. Sure, app developers have to adapt their software to new Android versions, voice their feedback, and can submit patches for bugs in Android, but have no power to enforce patches are picked & rolled out. In the topic about crahes I just posted that I downgraded from Locus 4.28 to Locus v4.23.1 and did not experience any more crashes for 3 weeks. If that was not just extreme luck but the ongoing behaviour, it's in 2 ways good news for the topic you currently read:

• For users affected by the crashes, until the Android library crashes are overcome, v4 is not any more just usable to experiment & play around with, but after installation of Locus v4.23.1, Locus 4 is fully usable, thus v3 as well as shared directory are not a required workaround any more. This massively changes point 3 of my comment 2025-03-03 to positive 🙂
• Hopefully, it's feasible to analyse the diff between 4.23.1 + 4.24.3 and change the way Locus calls the library, so no crashes happen any more. This would allow also the users affected by the crashes to update to latest Locus version, i.e. they get a long term perspective and point 3 of my comment 2025-03-03 becomes completely redundant 🙂

3. I can confirm points + tracks were restored from v4.28's backup in both v4.23.1 and v3.70

Additionally to the steps I mentioned, a few more are relevant. To make the process easier for other users, could you please extend manual in section "Recent versions of Locus Map" by:

• Choose which Locus version you want and download the APK for your system (Google Play, Google Play AFA, Amazon)
• In Locus, create a manual backup
• Uninstall your current Locus version. You can try to keep your app data, but it may be incompatible with the target version of Locus.
• Disable auto-updates in the app manager, e.g. Google Play Store, to avoid the manually installed version is replaced by current version
• Reboot your device. Without that, installation may fail without any error message:
• Install the downloaded APK
• Start Locus and if in need for, restore points, tracks and maybe more from backup

4. OK

5. As I have sensitive data in my library, I'd prefer to try to re-create the issue with a demo data set. Before I do so: Is this issue still relevant / new for you?

Best regards,

Georg