Yesterday my Lumia 640 (running Windows 10 Mobile 1703) restarted several times in the off-hours. I was thinking it just installs updates, but as far as I can tell there were no updates installed.
But since that, a number of apps in the app list now have a subtitle that reads "Pending". So of the apps are back to life if I click them others just refuse to start. I have an SD Card inserted and think this could be SD card related. But maybe not. I have set to install new apps to Phone (but some of the apps may have been installed before on the SD card). Who knows that behavior, what does it mean?