DF1 protocol app

I've developed an app to read/write data to Allen Bradley PLCs via serial DF1 communication protocol via Bluetooth.
I will appreciate any feedback. The app is available in Google Play as an open testing release. The most important features are available for free. If you wish to test the Pro version, just send me an email and I will reply with a promo code so you can upgrade for free.

Google Play: https://play.google.com/store/apps/details?id=com.facsocubac.df1polling&hl=en_US&gl=US

Please watch the instructions video in Google Play before using it.

Thank you for your help.