Android Pro app resets completely

[Jacob Wall]

Curious if anyone has experienced similar issues with their Android Pro app:
1. User apps disappear for no reason
2. Calculator settings are completely reset for no reason
3. Other similar loss of data/settings?

I have tried to reproduce the issue consistently, but with no success yet. Most of the time I will use the hardware calculator, but occasionally I only have the Android with me (Pixel 2, Android 8.1), only to find that the user apps I installed on there are gone and all the settings are back to factory defaults. This has happened about 3 or 4 times in the past two months, only on the Pixel 2. On another Android Device, Samsung Tab E (Android 7.1.1) I haven't had any issues.

Other observations:

1. Updates
When the Android app was recently updated, I checked and was surprised that all the settings and user apps were unaffected after the update, so I certainly can't pin this to an update issue, and I know I haven't purposely reset the calculator.

2. Resets
A Reset from the menu Calculator>Reset clears all user apps, but that is expected. A Reset also leaves the Serial number intact, and the app will re-connect to the Connectivity Kit automatically. During the loss of memory situations, I have seen the Serial number changed, and I'll have to go and choose "HP_Classroom" before I am able to connect to the Connectivity Kit again.

Interestingly, as I was typing this post and playing around with the Pixel 2, it happened again, serial number changed, everything reset. Attempting to reproduce is not yielding any results however.

[Arno K]

I do not encouter problems like that, but, as I usually seldom use the Pro App, it has difficulty finding the conkit, only after a restart of the smartphone the network is found (Huawei P10plus, Android Oreo)
Arno

[goetz]

On a similar configuration (Pixel with Android 8.1), I also had that effect recently. Like you described, since the recent update on FW 13443, all the content was kept intact. Now from time to time the HP Prime Pro App will clear Apps and other data, and I am not able to reproduce this. It also does not seem to be connected to corruption of the data after update, as I have cleared the app's data via the system settings (not only cache) and the problem still occurs.

As a workaround: When I had the issue with my apps disappearing I noticed that the backup on the HP Prime in the "Mem" menu was still there. I could restore everything with a few key presses. Performing a local backup on the HP Prime Pro app may work as a workaround against such cases.

[Arno K]

So you were lucky, I now made a backup on my phone, too (one never knows), I usually only connect if there are changes to be made, which is quite seldom on the phone and then I make a new backup with the connkit. Sorry that I can't help you with your problem but perhaps that may disappear after a total reset of the phone, perhaps some update of Android may have caused the instability.
Arno

[StephenG1CMZ]

The fact that the serial number changes has me wondering whether the Android might be clearing the HP Prime Pro App's cache...I imagine that would also lose language settings.
Perhaps it is not what you are doing within the App, but what is happening on the Android.
Just an idea. Next time it happens, is the Android App cache empty? Would it be empty anyway after a reset of the Prime?

[goetz]

Interesting idea. Just cleared the cache of the app manually. Result: language settings and backups are still there, but all apps, programs, and variables are gone. So that is the same effect like described above.

I wonder why the user data is stored in the cache, it should not be stored there, but in the normal app storage, and the cache only be used for data the app can recreate on its own without data loss.

[Arno K]

Ok, I think because it is/was convenient to store data there due to system restrictions invented by Google some tims ago, it was Android 4 or 5 when they decided not to let any app store and read data anywhere on the device. Now apps need special right to access folders other than their own. Perhaps Tim can give the prime app a folder for storing content now.
Nevertheless we found out why your Android prime loses data from time to time.
Arno

[Jacob Wall]

Can't say I'm terribly familiar with Android app file management, but to the best of my knowledge I would have to root my device in order to browse the /data/data/ folder where the apps store all their data. I don't have a Android development environment setup on my PC, perhaps there would be other methods through those tools.

Going in through Settings>Storage>Other Apps>HP Prime Pro I did some tests:
1. With the Clear Cache option, my user apps remained, everything was functional still when restarting the app.
2. With the Clear Data option, everything was removed, (just like the warning suggested). When I launched the app I saw the "Slide to Unlock" message, followed by choosing language and initial setup steps. It was as if the app was completely removed and installed for the first time. New serial, etc, and I had to reboot the Android device before I could connect to Connectivity Kit.

The "Reset" option within the app does some other customized (?) operation that removes user apps and resets user settings to default.

The random reset seems to be different from all the possible user-initiated procedures, because even though it completely resets user apps and settings, serial #, and possible other data, it does not present me with the "first run" type of setup steps.

I agree, this appears to be Android OS related, and probably caused by a change introduced in Android 8.

[Arno K]

What one often reads about are unstabilities caused by updates of Android, most recommendations to help are total resests. I never did such a reset and, luckily, never had any issues.
Arno

[goetz]

Just out of curiosity, I tried clearing the cache again, and all my installed Prime apps and variables are still there. While I tried that successfully a couple of times before, unfortunately it does not work and does not seem related to clearing the cache. Please disregard my notes about that above.

I remember the same issue with the HP Prime Pro application when I first bought the app in August 2016 and the android device was on Android 7.0 (or was it 7.1?). In 2016 (or 2017 (?)) an update for HP Prime Pro appeared on the Play store stating that it solved the problem and indeed it did. Strange

Those advices with a factory reset after the update probably refer mainly to 3rd party Android versions and also mostly relate to cases that can be fixed by deleting chache and/or some of the settings only. That is also one reason that I stick to stock Android on Nexus/Pixel devices, so I don't have to bother with such things and drastic procedures.

Luckily, the workaround with the local Backup within the Prime Pro up still works nicely.