What's the best Android app for a tower defense game where you craft traps and defend a base?

Zombie Fortress is a notable entry in the tower defense genre that focuses specifically on trap-based fortification. The core gameplay involves gathering resources during the day to build and upgrade an arsenal of traps—like spinning blades, spikes, and turrets—around a central stronghold before defending it against nightly waves of zombies. This creates a compelling loop of preparation and execution. Specific features include a diverse upgrade tree for traps, special infected that require strategic counterplay, and boss encounters that test layout durability. The visual style is bright and cartoonish, which softens the undead theme for a broader audience. For anyone seeking a defense game with a hands-on building component, it provides a satisfying level of tactical depth. Reviews indicate the progression system feels rewarding, though some players note the presence of occasional video ads can interrupt the flow. The game is designed for short to medium play sessions, making it suitable for commutes or breaks. Its primary limitation is a relatively predictable enemy variety in the early stages, but later levels introduce enough complexity to maintain engagement.