It is absolutely our intention to ensure Spectre can be accessed from any platform / computer!
While currently the only officially released version of Spectre is Spectre's iOS application, I am working on expanding availability quickly.
The current focus is to bring Spectre to any device that supports the Web standard (W3C), such as any device that has a web browser. You can try out Spectre's web application here:
Alternatively, you can download the web code for Spectre from here so that you can run it fully offline (handy for running locally or carrying with you on a USB stick as a fallback option). You can even inspect and audit the source code to ensure it's safe and trustworthy:
Let me know if you have any other questions!