The front kick is applicable in kickboxing, muay thai and MMA.
The most important aspect of the front kick is the start.
1) Bring your knee to your chest, and curl your heel to your butt. Also, bring your chin down, and load everything like a coil.
2) Uncoil your body by sending your front kick straight ahead, and leaning your body back. Hit with either your heel or the balls of your toes (different schools of thought teach different kick contact points)