I need to debug an Android app that uses USB Host mode to talk to Arduino. It looks like Android Studio Virtual Devices don't have USB, so I need a hardware device to debug my app. The problem is every phone I know has only one USB port, which is used both for charging and for talking to other devices. But when the USB port is in the Host mode it provides the power to the other device, and can't be charged. Are there any Android devices that can be charged while in USB Host mode? Or else, how do people debug USB Host apps.
I think I have found an Android device that solves this problem - ASUS Tinker Board. It has a micro USB connector for incoming power, and it has 4 USB ports that work in Host mode.