It does indeed affect 0.15.90.2
I have a little information that might help. The zombie pigmen appear to spawn in the portals, but the instantly teleport to the nether after they spawn. They need a cool down when they spawn that prevents them from teleporting right after they spawn.
I can confirm this bug on 0.15.1, on a galaxy s4 android 5.1.1.
Confirmed on Samsung Galaxy S4 on MCPE 0.15.1
Confirmed on Galaxy S4
Is your Google Play Services up to date?
Is there any way to get the coordinates? I would like to confirm for myself Mega_Spud.
Confirmed in 0.14.3. Crops indeed should pop when there is 0 light level. This breaks one farm that I know of, but there are others that can replace it.
I can confirm this on 0.14.3. I have never seen a cave spider spawner in mcpe. I'm a pretty avid player, an I've been through quite a few mineshafts; and I would have expected to see one by now.
I can reproduce on Galaxy S4, android 5.1.1
This bug has been resolved.
I can confirm on Galaxy S4 running Cyanogenmod 12.1 (Android 5.1.1).
Redstone shouldn't get cut off by transparent blocks at all. I can't confirm this bug at all.
Confirmed on Samsung Galaxy S4 running Cyanogenmod 12.1 (Android 5.1.1)
MCPE 0.13.0 full release.
Confirmed on Samsung Galaxy S4 running Cyanogenmod 12.1 (Android 5.1.1).
This bug is still occurring on 0.13.0 build 3
Confirmed to affect 0.12.2 on Galaxy S4 running Cyanogenmod 12.1 (Android 5.1.1 (aosp)).
To fix this try to update an app called "Android System WebView" from the app store. This fixed the problem for me and at least one other person.