Older devices might experience lag during large battles. Lowering game resolution within the settings can help.
Since there is no direct, official port of the original Stronghold Crusader (2002) by Firefly Studios on the Google Play Store, community-driven repacks are the primary way to play the classic desktop experience on Android. Why Play Stronghold Crusader on Android? stronghold crusader apk data android repack
Additionally, use (requires root) to emulate a lower GPU profile, forcing the game to run in OpenGL ES 1.1 mode instead of 2.0. Older devices might experience lag during large battles