Ask HN: How can I test my VPN client on more Android and Windows devices?

I'm developing a cross-platform VPN client. Because the primary design goal is censorship circumvention, I'm using a custom protocol and cannot just put a wrapper around existing, well-tested, open-source solutions.

For iOS/macOS, once I've got the client working well on my own test devices, it generally works fine for other users. Unfortunately this isn't the case for Android or Windows. Even though the client works flawlessly on the devices I have available to test locally, many real-world users see poor performance or can't get it working at all.

While I always try to work with users to identify and fix the issues, most of them (understandably) prefer to just get a refund and switch to another VPN. So if I could do in-depth testing on a broader range of devices it would boost retention considerably.

Ideas I've considered so far for expanding my testing pool:

- Hire testers on a site like Fiverr

- Offer free accounts for testers

- Use a "real device cloud" testing service

- Hire a more experienced VPN developer with expertise on those platforms

- Open source the client code to get more developer eyes on it