Decent Sampler

Decent Sampler is the first one I would install because the free library ecosystem is so active. dslibrary) and runs on Windows, macOS, Linux, and iOS. On desktop, it works as a VST, VST3, AU, AAX, and standalone app where supported. The big reason to install it is Pianobook. Many Pianobook libraries are available in the Decent Sampler format, giving you instant access to pianos, pads, strings, plucked instruments, toy keyboards, field-recorded oddities, lo-fi textures, and cinematic sound design tools.

I also like Decent Sampler because individual libraries feel like small custom plugins, similar to Kontakt. Developers can build their own interface with artwork, knobs, sliders, and controls, so loading a good Decent Sampler library feels more polished than opening a raw sample mapping. The limitation is that Decent Sampler is a playback engine, not a full sampler editor. You can build instruments for it, but you are working inside the Decent Sampler format rather than a universal standard.