Device is not listed but is the LG/Google Nexus 5, Android 4.4 Kit Kat, unmodified.
What I expected to happen was...:
Placing TNT and hitting with flint and steel while in vicinity of a minecart should cause explosion and damage to rails...
What actually happened was...:
While placing TNT works under normal circumstances in an unchanged piece of land, when I placed TNT beside an area with rail, redstone rail and a moving or stationary mine cart, upon lighting the TNT at the point of explosion the game crashed. I have tried this a number of times and each time the result is the same.
Note - No crashes when just rail or powered rail is placed, just when a minecart is on the rail.
Steps to Reproduce:
1. Place a loop of rail and/or powered rail down
2. Place a minecart on the rail
4. Place TNT
5. Flint and Steel the TNT
6. Enjoy crash.
I've included a screenshot and will also report the crash from the device