Kindle app disabled after every reboot..

[moyesboy]

I have a new Lenovo tab2 and on it the kindle app will not stay enabled.
I install it, it works. But after a reboot the app is not listed under settings. It is listed under my apps/all on google play (if wifi is connected) as disabled. If I enable it, it works, and all settings are retained. But that is impossible without wifi coverage.
After the reboot the app icon is there but it is erased after a few seconds, even if I manage to tap it in time and the app is stating to load! the result is the same - app is disabled. What a tease it is!

Things I tried so far:
rebooting lots of times.
Factory reset
checked app is latest version (it is of course, as it was from google play...)
Deleting all installed apps as far as possible (no change)
More factory resets
Deleted all but one kindle device in accounts (then found it cant be this as same happens with no account registered in app, or a different kindle account registered)
Rebooted with wifi off - still disabled. Its not disabled due to something its being told to do via wifi...
Loaded dec 2013 version kindle app from apk (from apk mirror, enabling apps from unknown sources). Still disables.

Result is always the same. Lenovo is running android 4.4.2
Tested kindle app on colleagues alternative nexus tab on android 5.0 and no issues there.
Kindle app also works fine on my Galaxys3 phone (Android 4.3)

Further device details: Lenovo tab2 A7-30F Android 4.4.2 kernel 3.4.67 RAM 1Gb ROM 8.00G 64Gb sd card (tried with and without that..)

Primary use of device was as an ereader! I might have to take it back to the shop - but how can I be sure the kindle app will work on a replacement device in advance? and without paying double what this one cost? (£59)

 

[B. Diddy]

Welcome to Android Central! Try booting into Safe Mode, which temporarily disables all 3rd party apps. On most Android devices, while powered on, press and hold Power until the Power Off menu appears. Press and hold the Power Off selection until the Safe Mode prompt appears. Tap OK.

If the problem disappears in Safe Mode, then something you installed is causing the problem. You may have to uninstall apps one by one until the problem disappears. If the problem persists in Safe Mode, then it's more likely to be a hardware or firmware problem.

 

[moyesboy]

I've already been into safe mode, and tried un installing all un installable apps...
So that might mean a of the fixed apps provided by the manufacturer is the problem, or there is some sort of hardware issue.
However the other apps I tried functioned correctly.
I've never come across such a unique issue - nobody else in the word seems to have this problem!
The android kindle app runs fine on my phone (samsung android 4.3) and a colleagues nexus tablet device (android 5.0)
Its very disappointing, but I will take it back tot he shop. For me the device is not fit for purpose - they will have to take it back because they (Argos.co.uk) spec it as android 5 but it isn't and there is no promise date from Lenovo for it ever to be upgraded from 4.4.3!