We make games using a 3rd party development platform that we have no control over. We do our best to make our games as efficient as possible, but we can’t do better than the limits of the game engine.
Also, games in general are very hard on mobile processors, and will always cause your phone to drain battery much faster than general use. To get around the battery problem, you can find battery packs for most smartphone models that can quadruple (or more) your battery life. And for powerful devices, you may get perfectly smooth gameplay, but dramatically improved battery life, by turning on Power-Saving Mode.