The Perception Grenade tags every enemy near where it lands. Throw one into a base before you go in so you know exactly where each guard is standing.
Throw it into the middle of a base or a building you plan to clear. You see every soldier around the landing spot, which makes planning a stealth route much easier.
Your phone camera can also tag enemies, but you have to scan each one. The Perception Grenade tags a whole area in one throw.
Bait
Bait is a chunk of meat you throw to draw predators to a spot. Toss it near FND soldiers and let the local wildlife do the fighting, or use it to bring out animals while hunting.
C4
C4 is a remote-detonated explosive you place and trigger when the moment is right. It is your best tool for setting traps on roads, wiping out parked vehicles or blowing up a target without being nearby.
Dynamite
Dynamite is a timed explosive built for wrecking vehicles rather than soldiers on foot. Throw it under an armored car or tank and get clear before the fuse runs out.
EMP Grenade
The EMP Grenade shuts down vehicles, cameras and alarms in its blast. Throw one before you sneak into a base to blind its security, or stop a vehicle dead in its tracks.