Not to be a Debbie downer but design wise it has issues both aesthetically and in its flow. It's hard to gauge the overall status in the order processing and functionality isn't presented in an easy to understand way. On top of that, the visual look is very dated and not very appealing. Both are relatively easy to fix and I can expand on the issues if you wish?
I was going to say, what version of Android is the demo video running? It looks like it's the Android design from 5 years ago. Definitely could use some UI enhancements.
That is a good point! Our workers have Android phones which are at least 6 years old. Later after the test period, I am planning to provide them with a tablet specifically for running this App.
My tip is not to use custom styling for buttons/text/etc just use the default Material design. It is already pretty nice, certainly better than what a non-designer can come up with. If you are interested in details, check out the design guidelines at https://material.io/, they cover a lot of stuffs from colors to padding sizes.
