1: check the SIM card number and deny access to those who do not have them. This includes tablets, as you have stated that you want to block them.
Java:
TelephonyManager telemamanger = (TelephonyManager) getSystemService(Context.TELEPHONY_SERVICE); String getSimSerialNumber = telemamanger.getSimSerialNumber(); String getSimNumber = telemamanger.getLine1Number();
Manifest.xml:
<uses-permission android:name="android.permission.READ_PHONE_STATE"/>
2. Checking the core of the emulator.
If # 1 fails due to user modifications to their emulator, check (ro.kernel.qemu == 1). This property is read-only and will always return 1 for emulators.
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