After an Ubuntu Touch update on a Volla Phone
to 16.04 OTA-17, the camera, music & weather app
(and maybe more) do not work anymore. 
(I'm not 100% sure, if this is related to the update,
since I also installed a bunch of apps, but the apps
started before.)
Starting the apps, after a short time there's
a spinning circle (to show that the app is busy),
but nothing happens.
After enabling the developer mode, remotely
login to the phone via ssh, I tried to start and
strace an app (while no other app was running)
like
$ ubuntu-app-launch com.ubuntu.camera_camera_3.2.3; strace -p `pgrep camera-app`
$ ubuntu-app-launch com.ubuntu.music_music_2.9.22; strace -p `pgrep qmlscene`
$ ubuntu-app-launch com.ubuntu.weather_weather_5.8.2; strace -p `pgrep qmlscene`
but all these attemps ended (after about 3940 lines) with
faccessat(AT_FDCWD, "/dev/hwbinder", R_OK|W_OK) = 0
clock_gettime(CLOCK_MONOTONIC, {XXXX, XXXXXXXXX}) = 0
and an endless repetition of the latter. Not sure, what the gettime spinlock is good for...
Does anyone have an idea what's going on here and
what can be done to find out?
Thanks,
Martin