I've had the same problem with a Kindle Fire HD 8 (2017 - Gen 7) since the beta test started. Works fine on my OnePlus 3 as expected.
At first I was suspicious it was a low memory issue, since these devices are fairly limited but even after disabling a lot of the stock amazon apps to free up a decent amount of memory it still crashes. You can also see in the logs further down that the OOM killer is not responsible for closing the app. It looks more like a memory allocation isn't aligned as it's expected to be.
Since the issue doesn't seem to have been acknowledged at all, here's an extract from the device logs that might help move things along a bit.
EDIT: Pastebin link doesn't seem to work. Mods PM me for it?
The key lines seem to be these:
F/libc (26089): Fatal signal 7 (SIGBUS), code 1, fault addr 0xfecb01b8 in tid 26131 (Thread-12575)
I/libc (26089): Suppressing debuggerd output because prctl(PR_GET_DUMPABLE)==0
I/Kernel (26089): [234695.802632] <0> (0)[26131:Thread-12575][name:fault&]Unhandled fault: alignment fault (0x92000061) at 0x00000000fecb01b8
I/Kernel (26089): [234695.803128] <0> (0)[26131:Thread-12575][name:fault&]Unhandled fault: alignment fault (0x92000061) at 0x00000000fecb01b8
I/WindowState( 532): WIN DEATH: Window{21b73dc u0 ***.jagex.runescape.android/***.jagex.android.MainActivity}
--------------------------------------------------------------------
W/ActivityManager( 532): Force removing ActivityRecord{21dfd2bd u0 ***.jagex.runescape.android/***.jagex.android.MainActivity t821}: app died, no saved state
W/Eve ( 532): MEMORY_LEVEL: [26089,0]
W/Eve ( 532): top=***.jagex.runescape.android/***.jagex.android.MainActivity launching=false
W/Eve ( 532): prev=***.teslacoilsw.launcher/.NovaLauncher screen_on=true thermal=0
W/Eve ( 532): adb=true downloading=false
W/Eve ( 532): memory=0 available=447032KB free=305360KB
W/Eve ( 532): Lmk did not kill ***.jagex.runescape.andro
30-Dec-2018 11:32:19
- Last edited on 30-Dec-2018 11:34:06 by Mazaron233