docs: function( options, callback ) {
        var me = this;
        var error = function(e) { fail(e); if ( callback ) me.fn( me.name, callback ).call( me, me ); };
        var size = options.size || 100*1024*1024;
        var name = this.name;
        //disable file backup to icloud
        me.backup = false;
        if(typeof options.backup !== 'undefined'){
          me.backup = options.backup;
        }
  
        function requestFileSystem(amount) {
  //        console.log('in requestFileSystem');
          var fs = global.requestFileSystem || global.webkitRequestFileSystem || global.moz_requestFileSystem;
          var mode = window.PERSISTENT;
          if(typeof LocalFileSystem !== "undefined" && typeof LocalFileSystem.PERSISTENT !== "undefined"){
            mode = LocalFileSystem.PERSISTENT;
          }      
          fs(mode, amount, function(fs) {
  //          console.log('got FS ', fs);
            fs.root.getDirectory( name, {create:true}, function( directory ) {
  //            console.log('got DIR ', directory);
              filesystems[name] = directory;
              if ( callback ) me.fn( me.name, callback ).call( me, me );
            }, function( e ) {
  //            console.log('error getting dir :: ', e);
              error(e);
            });
          }, function( e ) {
  //          console.log('error getting FS :: ', e);
            error(e);
          });
        };
  
        // When in the browser we need to use the html5 file system rather than
        // the one cordova supplies, but it needs to request a quota first.
        if (typeof navigator.webkitPersistentStorage !== 'undefined') {
          navigator.webkitPersistentStorage.requestQuota(size, requestFileSystem, function() {
            logger.warn('User declined file storage');
            error('User declined file storage');
          });
        } else {
          // Amount is 0 because we pretty much have free reign over the
          // amount of storage we use on an android device.
          requestFileSystem(0);
        }
      }