My Manifest file (permissions & support-screens) are as follow :

<uses-sdk
        android:maxSdkVersion="17"
        android:minSdkVersion="10"
        android:targetSdkVersion="17" />

    <permission
        android:name="com.ecw.healow.permission.C2D_MESSAGE"
        android:protectionLevel="signature" />

    <uses-permission android:name="my_app_package.permission.C2D_MESSAGE" />
    <!-- App receives GCM messages. -->
    <uses-permission android:name="com.google.android.c2dm.permission.RECEIVE" />
    <!-- GCM requires a Google account. -->
    <uses-permission android:name="android.permission.GET_ACCOUNTS" />
    <!-- Keeps the processor from sleeping when a message is received. -->
    <uses-permission android:name="android.permission.WAKE_LOCK" />
    <uses-permission android:name="android.permission.INTERNET" />
    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
    <uses-permission android:name="android.permission.ACCESS_MOCK_LOCATION" />
    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.READ_CALENDAR" />
    <uses-permission android:name="android.permission.WRITE_CALENDAR" />
    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
    <uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
    <uses-permission android:name="android.permission.CHANGE_WIFI_STATE" />
    <uses-feature android:name="android.hardware.camera" android:required="true"/>
    <supports-screens
        android:anyDensity="true"
        android:largeScreens="true"
        android:normalScreens="true"
        android:smallScreens="true" />

上传到Play商店后，它不会显示NEXUS-7作为支持的设备。 任何的猜测？

After uploading to play store, It doesn't shows nexus-7 as supported device. Any guess?

推荐答案

在了Nexus 7有一个前置摄像头，每Getting您的应用程序准备果冻豆，需要一个摄像头意味着你的应用程序将显示带有如果你想要的Nexus 7的兼容性。要求=假了Nexus 7.设置为不兼容

While the Nexus 7 has a front facing camera, per Getting Your App Ready for Jelly Bean, requiring a camera means your application will show as incompatible with the Nexus 7. Set required="false" if you want Nexus 7 compatibility.

要确保你有一个可用的相机启动任何相机相关的功能之前，你可以检测设备是否具有摄像头硬件。

To ensure you have a camera available before starting any camera related features, you can detect whether the device has camera hardware.