req.body can't be read as an array

req.body isn't an array, but an object with two properties. This is evident from the console.log output you've provided. Therefore, it has no length property and no forEach method.

If it had been an array, it would have looked like this:

[ 
   { 
     deviceType: 'iPad Retina',
     guid: 'DF1121F9-FE66-4772-BE74-42936F1357FF',
     is_deleted: '0',
     last_modified: '1970-12-19T06:01:17.171',
     name: 'test1',
     projectDescription: '',
     sync_status: '1',
     userName: 'testUser' 
   },
   { 
     deviceType: 'iPad Retina',
     guid: '18460A72-2190-4375-9F4F-5324B2FCCE0F',
     is_deleted: '0',
     last_modified: '1970-12-19T06:01:17.171',
     name: 'test2',
     projectDescription: '',
     sync_status: '1',
     userName: 'testUser' 
   } 
]

To iterate over the keys of the object you have, you can use the construct

for(var key in req.body) {
  if(req.body.hasOwnProperty(key)){
    //do something with e.g. req.body[key]
  }
}

forEach is defined only for Arrays.

You need to use for...in loop instead:

for (var key in req.body) {
  if (req.body.hasOwnProperty(key)) {
    item = req.body[key];
    console.log(item);
  }
}