App store updatesOne way I've been monitoring this company activity is how frequently they update their apps on both the Google and Apple stores. The Android version was last updated on October 11, 2017 (Bug fixes and performance improvements) while the Apple version was on October 19, 2017 (PDF file viewing bug fix).
The fact that they continue to maintain and update the apps tell me there is SOME activity. Whether it translates to more customers or not is pure speculation. I am bit optimistic and hope these updates are a good sign that testing customers are using the app and providing valuable feedback.
Android Play Store: https://play.google.com/store/apps/details?id=com.hydragen.hydragenandroid
Apple App Store: https://itunes.apple.com/us/app/hydragen/id1206470816?mt=8