Installing the APK on a device will result in limited capabilities (no silent app install, no rebooting, no IMEI or serial number detection). See more details here:
https://h-mdm.com/headwind-mdm-capabilities/#mode
To get all required permissions, you need to grant the "Device Owner" rights to the Headwind MDM applications.
There are two ways to install Headwind MDM in the device owner mode (MDM mode) without using a QR code based installer.
1. Use adb to grant the device owner rights manually. See here how to:
https://qa.h-mdm.com/1411/ This method is time-consuming and in general it's not suitable for production purposes.
2. Request platform keys by the firmware manufacturer and sign the APK with these keys (if you have purchased the Enterprise license, you can ask Headwind MDM staff to sign the APK for you).