Trials Frontier is an adaptation for mobile devices of the Trials series as a free-to-play title with in-app purchases. The game uses the Old West setting of the American frontier, but also incorporates modern environments. The protagonist is a stunt biker who uses the rocky environments to ride. In one of the early levels he gets trapped under rocks after an explosion and is brought to a town. There he receives a new bike and helps out different characters to map the world and complete missions.
The gameplay is largely identical to the earlier games. In 2.5D side-scrolling levels the biker needs to reach the finish by crossing gaps, going up slopes and overcoming obstacles in the environment without losing balance. Two arrows in the bottom right corner of the screen are used to accelerate and brake. There are also two arrows in the bottom left corner to lean, perform mid-air flips and maintain balance. After crashing, an arrow in the top right corner can be tapped to recover. The player is rewarded with coins for completing checkpoints without crashing. It is also possible to compete against the ghost runs of friends.
The Home Village is the central hub. In the saloon there are different characters that offer missions and there is a garage to upgrade the bike. Two types of currencies are used: coins (basic) and gems (premium). Coins are mainly used to upgrade the bike through four types of parts that influence top speed, acceleration, lean and grip. Gems can be used to speed up upgrading. There is also an energy system based on fuel. Each mission and each restart costs fuel. When there is no more available the player has to wait or buy additional fuel as an in-app purchase. Completing missions by achieving the objectives or performing tricks is rewarded with coins and experience for a global level. Many missions have conditions such as a time limit, a specific type of stunt, beating a rival or limited the amount of crashes. At the end of the level a loot wheel can usually be spun to gain parts. Earning parts reduces the upgrading cost significantly. The chances of receiving a specific item can be raised by spending gems as this increases the area on the wheel of the desired item. Other elements that come into play later in the game are blueprints for new bikes, super magnets, rarified fuel, chips, showdown tickets and crafting parts into better ones.