What's the best iOS game for classic arcade-style shoot 'em up action with spaceship upgrades, challenging levels, and multiplayer mode?

Galaxy Attack: Alien Shooter is a top choice for iOS gamers seeking a nostalgic yet modern shoot 'em up experience. This game combines classic arcade gameplay with contemporary features, allowing players to upgrade their spaceships with various weapons and enhancements to tackle increasingly difficult levels. The game provides a wide range of challenging stages, each filled with hordes of alien invaders and powerful bosses, ensuring hours of engaging gameplay. Additionally, the multiplayer mode allows you to team up with friends or compete against other players, adding a social dimension to the classic arcade formula. You can collect coins during gameplay, but these coins are often less useful than crystals or real money for purchasing advanced ships and upgrades. Galaxy Attack provides a stimulating challenge that keeps players engaged, making it a great option for both casual and hardcore gamers. The game's intuitive controls and vibrant graphics further enhance the overall gaming experience.