diff --git a/lib/exceptions/no_such_entry_exception.dart b/lib/exceptions/no_such_entry_exception.dart
new file mode 100644
index 00000000..d6b3fea6
--- /dev/null
+++ b/lib/exceptions/no_such_entry_exception.dart
@@ -0,0 +1 @@
+class NoSuchEntryException implements Exception {}
diff --git a/lib/models/measurements/measurement_category.dart b/lib/models/measurements/measurement_category.dart
index 79f53140..c58c794d 100644
--- a/lib/models/measurements/measurement_category.dart
+++ b/lib/models/measurements/measurement_category.dart
@@ -7,7 +7,7 @@ part 'measurement_category.g.dart';
 @JsonSerializable(explicitToJson: true)
 class MeasurementCategory extends Equatable {
   @JsonKey(required: true)
-  final int id;
+  final int? id;
 
   @JsonKey(required: true)
   final String name;
@@ -15,10 +15,8 @@ class MeasurementCategory extends Equatable {
   @JsonKey(required: true)
   final String unit;
 
-  @JsonKey(
-    defaultValue: [],
-  )
-  List<MeasurementEntry> entries;
+  @JsonKey(defaultValue: [], toJson: _nullValue)
+  final List<MeasurementEntry> entries;
 
   MeasurementCategory({
     required this.id,
@@ -27,6 +25,20 @@ class MeasurementCategory extends Equatable {
     this.entries = const [],
   });
 
+  MeasurementCategory copyWith({
+    int? id,
+    String? name,
+    String? unit,
+    List<MeasurementEntry>? entries,
+  }) {
+    return MeasurementCategory(
+      id: id ?? this.id,
+      name: name ?? this.name,
+      unit: unit ?? this.unit,
+      entries: entries ?? this.entries,
+    );
+  }
+
   // Boilerplate
   factory MeasurementCategory.fromJson(Map<String, dynamic> json) =>
       _$MeasurementCategoryFromJson(json);
@@ -34,5 +46,8 @@ class MeasurementCategory extends Equatable {
   Map<String, dynamic> toJson() => _$MeasurementCategoryToJson(this);
 
   @override
-  List<Object> get props => [id, name, unit, entries];
+  List<Object?> get props => [id, name, unit, entries];
+
+  // Helper function which makes the entries list of the toJson output null, as it isn't needed
+  static _nullValue(_) => null;
 }
diff --git a/lib/models/measurements/measurement_category.g.dart b/lib/models/measurements/measurement_category.g.dart
index ebed3f19..315a40d2 100644
--- a/lib/models/measurements/measurement_category.g.dart
+++ b/lib/models/measurements/measurement_category.g.dart
@@ -9,7 +9,7 @@ part of 'measurement_category.dart';
 MeasurementCategory _$MeasurementCategoryFromJson(Map<String, dynamic> json) {
   $checkKeys(json, requiredKeys: const ['id', 'name', 'unit']);
   return MeasurementCategory(
-    id: json['id'] as int,
+    id: json['id'] as int?,
     name: json['name'] as String,
     unit: json['unit'] as String,
     entries: (json['entries'] as List<dynamic>?)
@@ -25,5 +25,5 @@ Map<String, dynamic> _$MeasurementCategoryToJson(
       'id': instance.id,
       'name': instance.name,
       'unit': instance.unit,
-      'entries': instance.entries.map((e) => e.toJson()).toList(),
+      'entries': MeasurementCategory._nullValue(instance.entries),
     };
diff --git a/lib/models/measurements/measurement_entry.dart b/lib/models/measurements/measurement_entry.dart
index 5609aa48..e46c87d3 100644
--- a/lib/models/measurements/measurement_entry.dart
+++ b/lib/models/measurements/measurement_entry.dart
@@ -7,7 +7,7 @@ part 'measurement_entry.g.dart';
 @JsonSerializable()
 class MeasurementEntry extends Equatable {
   @JsonKey(required: true)
-  final int id;
+  final int? id;
 
   @JsonKey(required: true)
   final int category;
@@ -35,5 +35,5 @@ class MeasurementEntry extends Equatable {
   Map<String, dynamic> toJson() => _$MeasurementEntryToJson(this);
 
   @override
-  List<Object> get props => [id, category, date, value, notes];
+  List<Object?> get props => [id, category, date, value, notes];
 }
diff --git a/lib/models/measurements/measurement_entry.g.dart b/lib/models/measurements/measurement_entry.g.dart
index cf116952..935487c7 100644
--- a/lib/models/measurements/measurement_entry.g.dart
+++ b/lib/models/measurements/measurement_entry.g.dart
@@ -10,7 +10,7 @@ MeasurementEntry _$MeasurementEntryFromJson(Map<String, dynamic> json) {
   $checkKeys(json,
       requiredKeys: const ['id', 'category', 'date', 'value', 'notes']);
   return MeasurementEntry(
-    id: json['id'] as int,
+    id: json['id'] as int?,
     category: json['category'] as int,
     date: DateTime.parse(json['date'] as String),
     value: json['value'] as num,
diff --git a/lib/providers/measurement.dart b/lib/providers/measurement.dart
index 29f84a11..70cc5bac 100644
--- a/lib/providers/measurement.dart
+++ b/lib/providers/measurement.dart
@@ -16,13 +16,18 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+import 'dart:convert';
+
 import 'package:flutter/material.dart';
 import 'package:http/http.dart' as http;
+import 'package:wger/exceptions/http_exception.dart';
 import 'package:wger/exceptions/no_result_exception.dart';
+import 'package:wger/exceptions/no_such_entry_exception.dart';
 import 'package:wger/models/measurements/measurement_category.dart';
 import 'package:wger/models/measurements/measurement_entry.dart';
 import 'package:wger/providers/auth.dart';
 import 'package:wger/providers/base_provider.dart';
+import 'package:wger/providers/helpers.dart';
 
 class MeasurementProvider with ChangeNotifier {
   static const _categoryUrl = 'measurement-category';
@@ -67,6 +72,7 @@ class MeasurementProvider with ChangeNotifier {
   /// Fetches and sets the measurement entries for the given category
   Future<void> fetchAndSetCategoryEntries(int id) async {
     final category = findCategoryById(id);
+    final categoryIndex = _categories.indexOf(category);
 
     // Process the response
     final requestUrl = baseProvider.makeUrl(_entryUrl, query: {'category': category.id.toString()});
@@ -75,7 +81,76 @@ class MeasurementProvider with ChangeNotifier {
     for (final entry in data['results']) {
       loadedEntries.add(MeasurementEntry.fromJson(entry));
     }
-    category.entries = loadedEntries;
+    MeasurementCategory editedCategory = category.copyWith(entries: loadedEntries);
+    _categories.removeAt(categoryIndex);
+    _categories.insert(categoryIndex, editedCategory);
     notifyListeners();
   }
+
+  /// Adds a measurement category to the remote db
+  Future<void> addCategory(MeasurementCategory category) async {
+    Uri postUri = baseProvider.makeUrl(_categoryUrl);
+    final Map<String, dynamic> newCategoryMap = await baseProvider.post(category.toJson(), postUri);
+    final MeasurementCategory newCategory = MeasurementCategory.fromJson(newCategoryMap);
+    _categories.add(newCategory);
+    _categories.sort((a, b) => a.name.compareTo(b.name));
+    notifyListeners();
+  }
+
+  /// Deletes a measurement category from the remote db
+  Future<void> deleteCategory(int id) async {
+    MeasurementCategory category = _categories.firstWhere((element) => element.id == id,
+        orElse: () => throw NoSuchEntryException());
+    int categoryIndex = _categories.indexOf(category);
+    _categories.remove(category);
+    notifyListeners();
+
+    final http.Response response = await baseProvider.deleteRequest(_categoryUrl, id);
+
+    if (response.statusCode >= 400) {
+      _categories.insert(categoryIndex, category);
+      notifyListeners();
+      throw WgerHttpException(response.body);
+    }
+  }
+
+  /// Adds a measurement entry to the remote db
+  Future<void> addEntry(MeasurementEntry entry) async {
+    Uri postUri = baseProvider.makeUrl(_entryUrl);
+
+    final Map<String, dynamic> newEntryMap = await baseProvider.post(entry.toJson(), postUri);
+    final MeasurementEntry newEntry = MeasurementEntry.fromJson(newEntryMap);
+
+    _categories.firstWhere((categories) {
+      if (categories.id == newEntry.category) {
+        categories.entries.add(newEntry);
+        categories.entries.sort((a, b) => b.date.compareTo(a.date));
+        notifyListeners();
+        return true;
+      }
+      return false;
+    }, orElse: () => throw NoSuchEntryException());
+  }
+
+  /// Deletes a measurement entry from the remote db
+  Future<void> deleteEntry(int id, int categoryId) async {
+    final int categoryIndex = _categories.indexWhere((category) => category.id == categoryId);
+    if (categoryIndex == -1) throw NoSuchEntryException();
+
+    final MeasurementEntry entry = _categories[categoryIndex]
+        .entries
+        .firstWhere((entry) => entry.id == id, orElse: () => throw NoSuchEntryException());
+    final int entryIndex = _categories[categoryIndex].entries.indexOf(entry);
+
+    _categories[categoryIndex].entries.removeAt(entryIndex);
+    notifyListeners();
+
+    final http.Response response = await baseProvider.deleteRequest(_entryUrl, id);
+
+    if (response.statusCode >= 400) {
+      _categories[categoryIndex].entries.insert(entryIndex, entry);
+      notifyListeners();
+      throw WgerHttpException(response.body);
+    }
+  }
 }
diff --git a/test/fixtures/measurement_categories.json b/test/fixtures/measurement_categories.json
index 5635f49f..12f8999f 100644
--- a/test/fixtures/measurement_categories.json
+++ b/test/fixtures/measurement_categories.json
@@ -1,9 +1,17 @@
 {
-    "count": 2,
-    "next": null,
-    "previous": null,
-    "results": [
-      {"id": 1, "name": "Strength", "unit": "kN"},
-      {"id": 2, "name": "Biceps", "unit": "cm"}
-    ]
+  "count": 2,
+  "next": null,
+  "previous": null,
+  "results": [
+    {
+      "id": 1,
+      "name": "Strength",
+      "unit": "kN"
+    },
+    {
+      "id": 2,
+      "name": "Biceps",
+      "unit": "cm"
+    }
+  ]
 }
\ No newline at end of file
diff --git a/test/fixtures/measurement_category.json b/test/fixtures/measurement_category.json
index c6b8b88b..3eff6658 100644
--- a/test/fixtures/measurement_category.json
+++ b/test/fixtures/measurement_category.json
@@ -1,21 +1,5 @@
 {
-  "count": 6,
-  "next": null,
-  "previous": null,
-  "results": [
-      {
-          "id": 1,
-          "category": 1,
-          "date": "2021-07-21",
-          "value": 10,
-          "notes": "Some important notes"
-      },
-      {
-          "id": 2,
-          "category": 1,
-          "date": "2021-07-10",
-          "value": 15.00,
-          "notes": ""
-      }
-  ]
+    "id": 1,
+    "name": "Strength",
+    "unit": "kN"
 }
\ No newline at end of file
diff --git a/test/fixtures/measurement_category_entries.json b/test/fixtures/measurement_category_entries.json
new file mode 100644
index 00000000..c6b8b88b
--- /dev/null
+++ b/test/fixtures/measurement_category_entries.json
@@ -0,0 +1,21 @@
+{
+  "count": 6,
+  "next": null,
+  "previous": null,
+  "results": [
+      {
+          "id": 1,
+          "category": 1,
+          "date": "2021-07-21",
+          "value": 10,
+          "notes": "Some important notes"
+      },
+      {
+          "id": 2,
+          "category": 1,
+          "date": "2021-07-10",
+          "value": 15.00,
+          "notes": ""
+      }
+  ]
+}
\ No newline at end of file
diff --git a/test/fixtures/measurement_category_toJson_without_id.json b/test/fixtures/measurement_category_toJson_without_id.json
new file mode 100644
index 00000000..4dd9dcf5
--- /dev/null
+++ b/test/fixtures/measurement_category_toJson_without_id.json
@@ -0,0 +1,6 @@
+{
+    "id": null,
+    "name": "Strength",
+    "unit": "kN",
+    "entries": null
+}
\ No newline at end of file
diff --git a/test/fixtures/measurement_entry.json b/test/fixtures/measurement_entry.json
new file mode 100644
index 00000000..4b841a25
--- /dev/null
+++ b/test/fixtures/measurement_entry.json
@@ -0,0 +1,7 @@
+{
+    "id": 3,
+    "category": 1,
+    "date": "2021-07-09",
+    "value": 15.00,
+    "notes": ""
+}
\ No newline at end of file
diff --git a/test/fixtures/measurement_entry_without_id.json b/test/fixtures/measurement_entry_without_id.json
new file mode 100644
index 00000000..34115721
--- /dev/null
+++ b/test/fixtures/measurement_entry_without_id.json
@@ -0,0 +1,7 @@
+{
+    "id": null,
+    "category": 1,
+    "date": "2021-07-09",
+    "value": 15.00,
+    "notes": ""
+}
\ No newline at end of file
diff --git a/test/fixtures/measurement_entry_wrong_category.json b/test/fixtures/measurement_entry_wrong_category.json
new file mode 100644
index 00000000..ac55ed5f
--- /dev/null
+++ b/test/fixtures/measurement_entry_wrong_category.json
@@ -0,0 +1,7 @@
+{
+    "id": 3,
+    "category": 83,
+    "date": "2021-07-09",
+    "value": 15.00,
+    "notes": ""
+}
\ No newline at end of file
diff --git a/test/measurements/measurement_category_test.dart b/test/measurements/measurement_category_test.dart
index 17d072ab..6a439029 100644
--- a/test/measurements/measurement_category_test.dart
+++ b/test/measurements/measurement_category_test.dart
@@ -35,6 +35,13 @@ void main() {
     'entries': [tMeasurementEntryMap],
   };
 
+  Map<String, dynamic> tMeasurementCategoryMaptoJson = {
+    'id': 123,
+    'name': 'Bizeps',
+    'unit': 'cm',
+    'entries': null,
+  };
+
   test('should convert a JSON map to a MeasurementCategory object', () {
     // act
     final result = MeasurementCategory.fromJson(tMeasurementCategoryMap);
@@ -48,6 +55,28 @@ void main() {
     final result = tMeasurementCategory.toJson();
 
     // assert
-    expect(result, tMeasurementCategoryMap);
+    expect(result, tMeasurementCategoryMaptoJson);
+  });
+
+  test('should copyWith objects of this class', () {
+    // arrange
+
+    MeasurementCategory tMeasurementCategoryCopied = MeasurementCategory(
+      id: 1234,
+      name: 'Coolness',
+      unit: 'lp',
+      entries: tMeasurementEntries,
+    );
+
+    // act
+    final result = tMeasurementCategory.copyWith(
+      id: 1234,
+      name: 'Coolness',
+      unit: 'lp',
+      entries: tMeasurementEntries,
+    );
+
+    // assert
+    expect(result, tMeasurementCategoryCopied);
   });
 }
diff --git a/test/measurements/measurement_provider_test.dart b/test/measurements/measurement_provider_test.dart
index 40577ef6..2979a934 100644
--- a/test/measurements/measurement_provider_test.dart
+++ b/test/measurements/measurement_provider_test.dart
@@ -1,9 +1,12 @@
 import 'dart:convert';
 
 import 'package:flutter_test/flutter_test.dart';
+import 'package:http/http.dart';
 import 'package:mockito/annotations.dart';
 import 'package:mockito/mockito.dart';
+import 'package:wger/exceptions/http_exception.dart';
 import 'package:wger/exceptions/no_result_exception.dart';
+import 'package:wger/exceptions/no_such_entry_exception.dart';
 import 'package:wger/models/measurements/measurement_category.dart';
 import 'package:wger/models/measurements/measurement_entry.dart';
 import 'package:wger/providers/auth.dart';
@@ -21,8 +24,24 @@ main() {
   late MeasurementProvider measurementProvider;
   late MockWgerBaseProvider mockWgerBaseProvider;
 
-  Uri tCategoriesUri = Uri();
+  String categoryUrl = 'measurement-category';
+  String entryUrl = 'measurement';
+  Uri tCategoryUri = Uri();
+  Map<String, dynamic> tMeasurementCategoryMap =
+      jsonDecode(fixture('measurement_category_entries.json'));
+  Uri tCategoryEntriesUri = Uri(
+      scheme: 'http',
+      host: 'tedmosbyisajerk.com',
+      path: 'api/v2/' + entryUrl + '/',
+      query: 'category=1');
+
   int tCategoryId = 1;
+  MeasurementCategory tMeasurementCategory =
+      MeasurementCategory(id: 1, name: 'Strength', unit: 'kN');
+  List<MeasurementCategory> tMeasurementCategories = [
+    MeasurementCategory(id: 1, name: 'Strength', unit: 'kN'),
+    MeasurementCategory(id: 2, name: 'Biceps', unit: 'cm')
+  ];
   Map<String, dynamic> tMeasurementCategoriesMap =
       jsonDecode(fixture('measurement_categories.json'));
 
@@ -30,9 +49,14 @@ main() {
     mockWgerBaseProvider = MockWgerBaseProvider();
     measurementProvider = MeasurementProvider(mockWgerBaseProvider);
 
-    when(mockWgerBaseProvider.makeUrl(any)).thenReturn(tCategoriesUri);
+    when(mockWgerBaseProvider.makeUrl(any)).thenReturn(tCategoryUri);
     when(mockWgerBaseProvider.fetch(any))
         .thenAnswer((realInvocation) => Future.value(tMeasurementCategoriesMap));
+
+    when(mockWgerBaseProvider.makeUrl(entryUrl, query: anyNamed('query')))
+        .thenReturn(tCategoryEntriesUri);
+    when(mockWgerBaseProvider.fetch(tCategoryEntriesUri))
+        .thenAnswer((realInvocation) => Future.value(tMeasurementCategoryMap));
   });
 
   group('clear()', () {
@@ -54,8 +78,7 @@ main() {
   group('findCategoryById()', () {
     test('should return a category for an id', () async {
       // arrange
-      MeasurementCategory tMeasurementCategory =
-          MeasurementCategory(id: 1, name: 'Strength', unit: 'kN');
+
       await measurementProvider.fetchAndSetCategories();
 
       // act
@@ -72,13 +95,6 @@ main() {
   });
 
   group('fetchAndSetCategories()', () {
-    String categoryUrl = 'measurement-category';
-
-    List<MeasurementCategory> tMeasurementCategories = [
-      MeasurementCategory(id: 1, name: 'Strength', unit: 'kN'),
-      MeasurementCategory(id: 2, name: 'Biceps', unit: 'cm')
-    ];
-
     test('should make a request url', () async {
       // act
       await measurementProvider.fetchAndSetCategories();
@@ -92,7 +108,7 @@ main() {
       await measurementProvider.fetchAndSetCategories();
 
       // assert
-      verify(mockWgerBaseProvider.fetch(tCategoriesUri));
+      verify(mockWgerBaseProvider.fetch(tCategoryUri));
     });
 
     test('should set categories', () async {
@@ -105,21 +121,8 @@ main() {
   });
 
   group('fetchAndSetCategoryEntries()', () {
-    String entryUrl = 'measurement';
-    Uri tCategoryEntriesUri = Uri(
-        scheme: 'http',
-        host: 'tedmosbyisajerk.com',
-        path: 'api/v2/' + entryUrl + '/',
-        query: 'category=1');
-    Map<String, dynamic> tMeasurementCategoryMap = jsonDecode(fixture('measurement_category.json'));
-
     setUp(() async {
       await measurementProvider.fetchAndSetCategories();
-
-      when(mockWgerBaseProvider.makeUrl(any, query: anyNamed('query')))
-          .thenReturn(tCategoryEntriesUri);
-      when(mockWgerBaseProvider.fetch(any))
-          .thenAnswer((realInvocation) => Future.value(tMeasurementCategoryMap));
     });
 
     test('should make a uri from a category id', () async {
@@ -167,4 +170,274 @@ main() {
       expect(measurementProvider.categories, tMeasurementCategories);
     });
   });
+
+  group('addCategory()', () {
+    MeasurementCategory tMeasurementCategoryWithoutId =
+        MeasurementCategory(id: null, name: 'Strength', unit: 'kN');
+    Map<String, dynamic> tMeasurementCategoryMap = jsonDecode(fixture('measurement_category.json'));
+    Map<String, dynamic> tMeasurementCategoryMapWithoutId =
+        jsonDecode(fixture('measurement_category_toJson_without_id.json'));
+    List<MeasurementCategory> tMeasurementCategoriesAdded = [
+      MeasurementCategory(id: 2, name: 'Biceps', unit: 'cm'),
+      MeasurementCategory(id: 1, name: 'Strength', unit: 'kN'),
+      MeasurementCategory(id: 1, name: 'Strength', unit: 'kN'),
+    ];
+    setUp(() {
+      when(mockWgerBaseProvider.post(any, any))
+          .thenAnswer((realInvocation) => Future.value(tMeasurementCategoryMap));
+    });
+
+    test('should post the MeasurementCategorie\'s Map', () async {
+      // act
+      await measurementProvider.addCategory(tMeasurementCategoryWithoutId);
+
+      // assert
+      verify(mockWgerBaseProvider.post(tMeasurementCategoryMapWithoutId, tCategoryUri));
+    });
+
+    test(
+        'should add the result from the post call to the categories List and sort the list by alphabetical order',
+        () async {
+      // arrange
+      await measurementProvider.fetchAndSetCategories();
+
+      // act
+      await measurementProvider.addCategory(tMeasurementCategoryWithoutId);
+
+      // assert
+      expect(measurementProvider.categories, tMeasurementCategoriesAdded);
+    });
+  });
+
+  group('deleteCategory()', () {
+    setUp(() async {
+      await measurementProvider.fetchAndSetCategories();
+    });
+    test(
+        'should remove a MeasurementCategory from the categories list for an id and call the api to remove the MeasurementCategory',
+        () async {
+      // arrange
+      when(mockWgerBaseProvider.deleteRequest(any, any))
+          .thenAnswer((realInvocation) => Future.value(Response('', 200)));
+
+      List<MeasurementCategory> tMeasurementCategoriesOneDeleted = [
+        MeasurementCategory(id: 2, name: 'Biceps', unit: 'cm')
+      ];
+
+      // act
+      await measurementProvider.deleteCategory(tCategoryId);
+
+      // assert
+      verify(mockWgerBaseProvider.deleteRequest('measurement-category', tCategoryId));
+      expect(measurementProvider.categories, tMeasurementCategoriesOneDeleted);
+    });
+
+    test('should throw a NoSuchEntryException if no category is found', () {
+      // act & assert
+      expect(() async => await measurementProvider.deleteCategory(83),
+          throwsA(isA<NoSuchEntryException>()));
+    });
+
+    test('should re-add the "removed" MeasurementCategory if call to api fails', () async {
+      // arrange
+      when(mockWgerBaseProvider.deleteRequest(any, any))
+          .thenAnswer((realInvocation) => Future.value(Response('{}', 400)));
+
+      // act & assert
+      expect(() async => await measurementProvider.deleteCategory(tCategoryId),
+          throwsA(isA<WgerHttpException>()));
+      // can't await the expect call above
+      await Future.delayed(Duration(milliseconds: 1));
+
+      expect(measurementProvider.categories, tMeasurementCategories);
+    });
+  });
+
+  group('addEntry()', () {
+    MeasurementEntry tMeasurementEntry = MeasurementEntry(
+      id: 3,
+      category: 1,
+      date: DateTime(2021, 7, 9),
+      value: 15.00,
+      notes: '',
+    );
+
+    MeasurementEntry tMeasurementEntryWithoutId = MeasurementEntry(
+      id: null,
+      category: 1,
+      date: DateTime(2021, 7, 9),
+      value: 15.0,
+      notes: '',
+    );
+
+    List<MeasurementCategory> tMeasurementCategories = [
+      MeasurementCategory(id: 1, name: 'Strength', unit: 'kN', entries: [
+        MeasurementEntry(
+          id: 1,
+          category: 1,
+          date: DateTime(2021, 7, 21),
+          value: 10,
+          notes: 'Some important notes',
+        ),
+        MeasurementEntry(
+          id: 2,
+          category: 1,
+          date: DateTime(2021, 7, 10),
+          value: 15.00,
+          notes: '',
+        ),
+        tMeasurementEntry
+      ]),
+      MeasurementCategory(id: 2, name: 'Biceps', unit: 'cm')
+    ];
+
+    setUp(() async {
+      await measurementProvider.fetchAndSetCategories();
+
+      Map<String, dynamic> measurementEntryMap = jsonDecode(fixture('measurement_entry.json'));
+      when(mockWgerBaseProvider.post(any, any))
+          .thenAnswer((realInvocation) => Future.value(measurementEntryMap));
+    });
+
+    test('should make the post url', () async {
+      // act
+      await measurementProvider.addEntry(tMeasurementEntryWithoutId);
+
+      // assert
+      verify(mockWgerBaseProvider.makeUrl(entryUrl));
+    });
+
+    test('should post the MeasurementEntryMap', () async {
+      // arrange
+      Map<String, dynamic> measurementEntryMapWithoutId =
+          jsonDecode(fixture('measurement_entry_without_id.json'));
+
+      // act
+      await measurementProvider.addEntry(tMeasurementEntryWithoutId);
+
+      // assert
+      verify(mockWgerBaseProvider.post(measurementEntryMapWithoutId, tCategoryEntriesUri));
+    });
+
+    test(
+        'should add MeasurementEntry to its MeasurementCategory in the categories List and sort the category\'s list by date',
+        () async {
+      // arrange
+      await measurementProvider.fetchAndSetCategoryEntries(tCategoryId);
+
+      // act
+      await measurementProvider.addEntry(tMeasurementEntryWithoutId);
+
+      // assert
+      expect(measurementProvider.categories, tMeasurementCategories);
+    });
+
+    test('should throw a NoSuchEntryException if no category is found', () {
+      // arrange
+      MeasurementEntry tMeasurementEntryWrongCategory = MeasurementEntry(
+        id: 3,
+        category: 83,
+        date: DateTime(2021, 7, 9),
+        value: 15.00,
+        notes: '',
+      );
+      Map<String, dynamic> measurementEntryMapWrongCategory =
+          jsonDecode(fixture('measurement_entry_wrong_category.json'));
+      when(mockWgerBaseProvider.post(any, any))
+          .thenAnswer((realInvocation) => Future.value(measurementEntryMapWrongCategory));
+
+      // act & assert
+      expect(() async => await measurementProvider.addEntry(tMeasurementEntryWrongCategory),
+          throwsA(isA<NoSuchEntryException>()));
+    });
+  });
+
+  group('deleteEntry()', () {
+    int tEntryId = 2;
+    List<MeasurementCategory> tMeasurementCategories = [
+      MeasurementCategory(id: 1, name: 'Strength', unit: 'kN', entries: [
+        MeasurementEntry(
+          id: 1,
+          category: 1,
+          date: DateTime(2021, 7, 21),
+          value: 10,
+          notes: 'Some important notes',
+        ),
+      ]),
+      MeasurementCategory(id: 2, name: 'Biceps', unit: 'cm')
+    ];
+
+    setUp(() async {
+      await measurementProvider.fetchAndSetCategories();
+      await measurementProvider.fetchAndSetCategoryEntries(tCategoryId);
+
+      when(mockWgerBaseProvider.deleteRequest(any, any))
+          .thenAnswer((realInvocation) => Future.value(Response('', 200)));
+    });
+
+    test('should remove a MeasurementEntry from the category\'s entries List for an id', () async {
+      // act
+      await measurementProvider.deleteEntry(tEntryId, tCategoryId);
+
+      // assert
+      expect(measurementProvider.categories, tMeasurementCategories);
+    });
+
+    test('should throw a NoSuchEntryException if the category isn\'t found', () {
+      // act & assert
+      expect(() async => await measurementProvider.deleteEntry(tEntryId, 83),
+          throwsA(isA<NoSuchEntryException>()));
+    });
+
+    test(
+        'should throw a NoSuchEntryException if the entry in the categories entries List isn\'t found',
+        () {
+      // act & assert
+      expect(() async => await measurementProvider.deleteEntry(83, tCategoryId),
+          throwsA(isA<NoSuchEntryException>()));
+    });
+
+    test('should call the api to remove the MeasurementEntry', () async {
+      // act
+      await measurementProvider.deleteEntry(tEntryId, tCategoryId);
+
+      // assert
+      verify(mockWgerBaseProvider.deleteRequest(entryUrl, tEntryId));
+    });
+
+    test(
+        'should re-add the "removed" MeasurementEntry and throw a WgerHttpException if the api call fails',
+        () async {
+      // arrange
+      List<MeasurementCategory> tMeasurementCategories = [
+        MeasurementCategory(id: 1, name: 'Strength', unit: 'kN', entries: [
+          MeasurementEntry(
+            id: 1,
+            category: 1,
+            date: DateTime(2021, 7, 21),
+            value: 10,
+            notes: 'Some important notes',
+          ),
+          MeasurementEntry(
+            id: 2,
+            category: 1,
+            date: DateTime(2021, 7, 10),
+            value: 15.00,
+            notes: '',
+          ),
+        ]),
+        MeasurementCategory(id: 2, name: 'Biceps', unit: 'cm')
+      ];
+      when(mockWgerBaseProvider.deleteRequest(any, any))
+          .thenAnswer((realInvocation) => Future.value(Response('{}', 404)));
+
+      // act & assert
+      expect(() async => await measurementProvider.deleteEntry(tEntryId, tCategoryId),
+          throwsA(isA<WgerHttpException>()));
+      // can't await the expect call above
+      await Future.delayed(Duration(milliseconds: 1));
+
+      expect(measurementProvider.categories, tMeasurementCategories);
+    });
+  });
 }