As seen from the release notes, the app will need to have Android 5.1.1 or higher for better working. So, Android 4.4 Device might fail. About Android 8.1, can you give us more details on which phone you are using. I do not know about the modifications you have made to the app. So, can you try to reproduce the issue with Cysmart Source Code?
Please connect the phone to Android Studio and run the OTA process. Share the logs present in the Logcat window.
Release notes can be found here: https://www.cypress.com/file/198626/download
the phone is Motorola E5 Play with os 8.1.
I have tried in this phone today both Cysmart app, the official apk and the source built in android studio 3.3.
The one from google playstore works, and the one compiled from source works only with target no over sdk 25, if 26 or over the problem of OTA not writing will happen.
No code was modified. The gradle is 3.0.1 and build tools v26.0.2.
Now google requires to target at least sdk 26 for app to distribute; to overcome this problem, can one request the newer source code for the OTA section of cysmart from cypress?
I think the source available from cypress website is still the same targeting sdk 22.
I see now there is the updated cysmart 188.8.131.526 source with minimum sdk 22 available, I was still running the cysmart 184.108.40.206 which caused my issue.