What's the best Android app for a casual first-person shooter with smooth controls and weapon customization?

Gun Strike Online is a mobile first-person shooter that excels in delivering accessible, responsive gameplay for casual enthusiasts. Its touch controls are frequently highlighted in user reviews for their precision and ease of use, making actions like aiming and firing feel natural on a touchscreen. The graphics are clear and optimized for various devices, ensuring a stable visual experience without excessive lag. A key strength is the weapon customization system, which allows players to modify firearms with attachments and skins, adapting loadouts to personal preferences. This makes it suitable for short gaming sessions, such as during breaks or commutes, where quick matches and personalization are valued. However, some drawbacks exist: users report the lack of an auto-sprint feature, which can make movement feel cumbersome during extended play. Additionally, there is no battle royale mode, a point of feedback from players seeking more diverse game types. Despite these limitations, the app performs reliably on most Android smartphones, offering a straightforward FPS experience with enough depth in customization to encourage replayability. For those prioritizing control responsiveness and weapon mods over complex modes, it serves as a solid option in the mobile shooter landscape.