Is there a web version free or just Desktop with Web instructions?

Yes — the free option is Genymotion Desktop for PC and Mac, not a separate web version. Genymotion Cloud products are available, but they are not free; only free trials exist. Is Genymotion free? Genymotion

The free edition is limited to personal use and has fewer features and no technical support. To start it, you download Desktop, choose “Personal Use,” and follow the online quick start guide. Is Genymotion free? Genymotion Desktop