I finally released a new version of my "Scientific Calculator" (now renamed to SciCalc). This release has a new interface, and more importantly, is available as a desktop app (using the Electron framework). There are currently builds for Windows x64, and Linux x64, Linux ARM (Raspberry Pi). The Chrome App version is still available, but I only recommend that for Chromebook users since Chrome will be discontinuing support for apps in the near future.
You can download it at https://www.scicalc.io.