When you're fiddling around in Creative, it's possible to use lava to set TNT blocks on fire. But, unlike survival (or any mode on the computer for that matter) they just melt away instead of kaboom-ifying.
MCPE-5588
TNT dissolving
Resolved
Fixed
0
(Unassigned)
Unconfirmed
Tablet - Android - Amazon Kindle Fire
fire, lava, melt, tnt
0.7.5, 0.7.6
0.8.0
Retrieved
Fixed in 0.8.0