Most changes in the app are provisioned with the settings, not part of the build. So for just about everything except changes in the white-label options or the white label specific theme options, you need to provision the editable settings to test.
How to do this will depend on your initial screen.
Classic (QR code scanner and username and password fields)
To provision the editable settings, reset the app and provision like
from the initial screen.
The * at the end of the cloud id is how the app knows to provision the editable settings.
Phone number registration wizard
Reset the app and add * to the end of the phone number when you log back into provision editable settings.
Web view registration wizard
For these options, you will need to adjust the provisioning links to include * at the end of the cloud id to provision the editable settings.
<a href="csc:username:password@CLOUDID*">Provision me</a>
For changes to white label options and the white label specific theme items, rebuild the app after making the change and install the new build.