diff --git a/src/app/services/helpers/store.service.spec.ts b/src/app/services/helpers/store.service.spec.ts
new file mode 100644
index 0000000..d70d649
--- /dev/null
+++ b/src/app/services/helpers/store.service.spec.ts
@@ -0,0 +1,88 @@
+
+import {ObservableCollectionHandler} from './store.service';
+import {IWSEvent} from '../../interfaces/ws.interface';
+import {BehaviorSubject} from 'rxjs';
+
+describe('Service: Observable Collection Handler', () => {
+
+  let subject: BehaviorSubject<any>;
+  let observable;
+
+  beforeEach(() => {
+    subject = new BehaviorSubject([]);
+    observable = subject.asObservable();
+  });
+
+  it('Should have an update method', () => {
+    expect(ObservableCollectionHandler.update).toBeDefined();
+  });
+
+  it('should add an element to the observable', (done) => {
+    const event: IWSEvent = {
+      model: 'Test',
+      msg: {
+        pk: 1,
+        changed_fields: [],
+        object: {id: 1, foo: 'bar'}
+      }
+    };
+
+    ObservableCollectionHandler.update(event, subject);
+
+    subject.subscribe(
+      (collection: any[]) => {
+        expect(collection.length).toBe(1);
+        expect(collection[0].foo).toEqual('bar');
+        done();
+      }
+    );
+  });
+
+  describe('when the subject already have content', () => {
+    beforeEach(() => {
+      subject.next([{id: 1, foo: 'bar'}, {id: 2, foo: 'baz'}]);
+    });
+
+    it('should update an element', (done) => {
+      const event: IWSEvent = {
+        model: 'Test',
+        msg: {
+          pk: 1,
+          changed_fields: [],
+          object: {id: 1, foo: 'updated'}
+        }
+      };
+
+      ObservableCollectionHandler.update(event, subject);
+
+      subject.subscribe(
+        (collection: any[]) => {
+          expect(collection.length).toBe(2);
+          expect(collection[0].foo).toEqual('updated');
+          done();
+        }
+      );
+    });
+
+    it('should delete an element', (done) => {
+      const event: IWSEvent = {
+        model: 'Test',
+        msg: {
+          pk: 1,
+          changed_fields: ['deleted'],
+          object: {id: 1, foo: 'deleted'}
+        }
+      };
+
+      ObservableCollectionHandler.update(event, subject);
+
+      subject.subscribe(
+        (collection: any[]) => {
+          expect(collection.length).toBe(1);
+          expect(collection[0].foo).toEqual('baz');
+          done();
+        }
+      );
+    });
+  });
+});
diff --git a/src/app/services/helpers/store.service.ts b/src/app/services/helpers/store.service.ts
new file mode 100644
index 0000000..80e8e05
--- /dev/null
+++ b/src/app/services/helpers/store.service.ts
@@ -0,0 +1,40 @@
+import {Injectable} from '@angular/core';
+import {IWSEvent} from '../../interfaces/ws.interface';
+import {BehaviorSubject} from 'rxjs';
+import * as _ from 'lodash';
+
+/**
+ * @whatItDoes Update a BehaviorSubject after receiving an event from an Observable
+ * @stable
+ */
+
+@Injectable()
+export class ObservableCollectionHandler {
+
+    static update(event: IWSEvent, subject: BehaviorSubject<any>): BehaviorSubject<any> {
+      const collection: any[] = subject.value;
+
+      const index: number = _.findIndex(collection, (i) => {
+        return i.id === event.msg.object.id;
+      });
+      const exist: boolean = index > -1;
+      const isDeleted: boolean = _.includes(event.msg.changed_fields, 'deleted');
+
+      // remove
+      if (exist && isDeleted) {
+        _.remove(collection, {id: event.msg.object.id});
+      }
+      // Replace item at index using native splice
+      else if (exist && !isDeleted) {
+        collection.splice(index, 1, event.msg.object);
+      }
+      // if the element is not deleted add it
+      else if (!exist && !isDeleted) {
+        collection.push(event.msg.object);
+      }
+
+      subject.next(collection);
+
+      return subject;
+    }
+}