Which Android app should I use for a long, offline tower defense game with hundreds of levels?

TDS is a strong contender for players seeking a substantial, offline tower defense experience. Its primary appeal lies in the sheer volume of content, with approximately 500 levels that provide a long-term progression curve. The core gameplay involves strategically placing and upgrading automated towers to defend against waves of zombies, a familiar but well-executed formula. A key feature for this use case is its fully offline functionality, making it suitable for commutes or areas with poor connectivity. Users report the initial and mid-game progression is satisfying, with a decent variety of towers and weapons to upgrade. However, reviews indicate some players encounter sudden difficulty spikes or bugs at specific levels, such as the 'Zombie Circus' around stage 75, which can disrupt the otherwise smooth progression. While the core loop can become repetitive over time—a common critique for games of this length—the offline access and depth of content outweigh this for many. The developer, SayGames Ltd, has shown responsiveness by removing the Wi-Fi requirement for launching the app, a change appreciated by the community. For anyone wanting a tower defense game to chip away at over weeks or months, TDS delivers a solid, content-rich package, though it's not without some occasional balancing quirks.