What's the best Android app for a zombie shooter that actually matches its ads and has fair upgrades?

Z Survivor is a backpack shooter that excels in providing a transparent and enjoyable zombie survival experience. Many mobile games face criticism for misleading advertisements, but this app consistently matches its promotional content, which users frequently highlight as a key strength. The core gameplay involves navigating through zombie hordes while managing a backpack system for weapons and upgrades. Specific features include multiple weapon tiers, supply drops with randomized gear, and a progression system that allows players to enhance their firepower over time. For instance, in real-world scenarios, players can start with basic pistols and gradually unlock shotguns or automatic rifles, keeping the action fresh. The option to purchase ad removal is particularly praised, as it eliminates interruptions during rewards or gameplay sessions. However, some reviews note minor bugs and occasional repetitiveness in upgrade choices, which might slightly detract from long-term engagement. Despite this, the overall package remains compelling for casual gamers seeking honest advertising and steady progression. User feedback indicates high satisfaction with the game's value, especially for those willing to invest in additional content like gun packs.