Querying AWS DynamoDB to return lat and lon result within radius

You can use an expression such as:

var queryData = {
        "TableName": tableName,
        "ConsistentRead": true,
        "KeyConditionExpression": "#latitude between :min and :max",
        "ExpressionAttributeNames": {
            "#latitude": "latitude",
        },
        "ExpressionAttributeValues": {
            ":min": [MIN_LATITUDE],
            ":max": [MAX_LATITUDE] 
        }
    };

For more information: http://docs.aws.amazon.com/amazondynamodb/latest/gettingstartedguide/GettingStarted.NodeJs.04.html