Even M5stickV has 3 buttons now. After an update, power button can be used to navigate(go back).
DIY version Dock navigates using a rotary encoder.
Yeah I know, but I have to admit that buttons are not very comfortable to use, if anyone plans to use them for entering letters and seed phrases manually DIY version Dock navigates using a rotary encoder.
I don't know how old Androids will handle the app. As the app doesn't require anything fancy I hope it has some wide range of compatibility. I have some cheap, but not old phones to test. If you try let us know if it worked.
I tried using Krux app with Android v4.4.2 and sadly it could not be installed on this old smartphone from year 2015.It works just fine in any newer smartphone and in android emulators.