If you have obtained a legitimate Dolphin Emulator APK , the setup process is straightforward: Are older versions available? - Dolphin Forums
Older versions occasionally have a smaller footprint on storage-constrained devices, with version 0.14 (a 4.0-era build) being as small as 10.47 MB . How to Install and Setup Dolphin Emulator 4.0 Apk
A complete overhaul of the OpenGL video back-end made the emulator compatible with GLES3, which was essential for the mobile devices of that era. If you have obtained a legitimate Dolphin Emulator