code: function deployToSim(appPath, target) {
      // Select target device for emulator. Default is 'iPhone-6' 
      if (!target) {
          return require('./list-emulator-images').run()
          .then(function (emulators) {
              if (emulators.length > 0) {
                  target = emulators[0];
              }
              emulators.forEach(function (emulator) {
                  if (emulator.indexOf('iPhone') === 0) {
                      target = emulator;
                  }
              });
              events.emit('log','No target specified for emulator. Deploying to ' + target + ' simulator');
              return startSim(appPath, target);
          });
      } else {
          return startSim(appPath, target);
      }
  }
docs: Deploy specified app package to ios-sim simulator
  @param  {String} appPath Path to application package
  @param  {String} target  Target device type
  @return {Promise}        Resolves when deploy succeeds otherwise rejects