Simulate your logic circuits through Qualsimm Logic Circuit Simulator Mobile app.
Easy to use.
The Best and Free Logic Circuit Simulator App.
This application is very useful for all engineering students and engineers.
List of available components:

AND gate
OR gate
NOT gate
NOR gate
NAND gate
XOR gate
XNOR gate
BUFFER gate
One Bit Monitor
Toggle Button
D Flip-Flop
T Flip-Flop
SR Flip-Flop
JK Flip-Flop
Low Constant
High Constant
Clock
4x1 Multiplexer
4x1 Demultiplexer
BCD to Seven Segment Decoder
Seven Segment Display
8x8 Led Matrix Display