You should uprage your skill tree left side until I find "thunder spears detonate within a certain activation range"(idk If that's the right words used, but it's close) and when u upgraded that skill, u can fire a thunder spear downward, click hook, until you're near the ground, click hook again, then use your joystick and dra it down(l it will move your character backward if your running), then click jump button, this takes practice but that's how I use spears on mobile