MouseDown MouseUP in Android

I have written a webapp that sends commands over the internet using an MQTT broker.
It will allow students at home to control a Goldenrod Research RoboArm in the classroom.

I deployed the app by creating a standalone project and installing it as a service on a computer in my network, then calling it up on my phone by going to

It seems to work well with Mac and Windows, but I thought I would try to pull it up with my phone just to see if it would work. It seems to work except for the mode1. This mode sends out a command to start the motor running in the mousedown event. Then when the button is released, the mouseup event sends a stop command. It works if I just click on the button with my finger without holding it down. The motor runs a few degrees. If I press and hold the button, nothing appears to happen.
Any ideas?