The tablet may not support some of the features that your app requires. You can make them “not required” for the app (that means that you should check if they are actually available before using them in the code).
It is done like that:
<!-- features -->
<uses-feature android:name="android.hardware.telephony" android:required="false" />
Other possible features are:
android.hardware.camera
android.hardware.camera.autofocus
android.hardware.location.gps
android.hardware.location
android.hardware.location.network
For full list of relations between features<->permissions, you can see:
http://developer.android.com/guide/topics/manifest/uses-feature-element.html
See “Feature reference”