Android has quite a capable emulation ecosystem. There are emulators for most major platforms, and frontends like Daijishou make the experience very user friend

Android has quite a capable emulation ecosystem. There are emulators for most major platforms, and frontends like Daijishou make the experience very user friendly. There's a plethora of handheld devices from Anbernic, Retroid and others, with built-in controllers, so no latency from BT, or you can just get something like a Razer Kishi for a regular phone. Modern chipsets are very fast and efficient, screens are large and high resolution, battery life is excellent, etc. We're really in the golden age of emulation on mobile devices.