Java tutorial
//package com.java2s; import android.os.Environment; import static android.os.Environment.MEDIA_MOUNTED; public class Main { public static boolean existSDcard() { String externalStorageState; try { externalStorageState = Environment.getExternalStorageState(); } catch (NullPointerException e) { // (sh)it happens (Issue #660) externalStorageState = ""; } catch (IncompatibleClassChangeError e) { // (sh)it happens too (Issue #989) externalStorageState = ""; } return MEDIA_MOUNTED.equals(externalStorageState); } }