diff --git a/README.md b/README.md
index 0101d7f..89847dc 100644
--- a/README.md
+++ b/README.md
@@ -1,14 +1,111 @@
 # checkbox_formfield
 
+[![pub package](https://img.shields.io/pub/v/checkbox_formfield.svg)](https://pub.dev/packages/checkbox_formfield)
+
 A few kinds of checkbox that can be used as FormField
 
 ## Getting Started
 
-This project is a starting point for a Dart
-[package](https://flutter.dev/developing-packages/),
-a library module containing code that can be shared easily across
-multiple Flutter or Dart projects.
+This library currently has two Widgets.
 
-For help getting started with Flutter, view our 
-[online documentation](https://flutter.dev/docs), which offers tutorials, 
-samples, guidance on mobile development, and a full API reference.
+* CheckboxListTileFormField: Use CheckboxListTile in Form
+* CheckboxIconFormField: Use two Icons as if they consist a checkbox and also in Form
+
+## Demo
+
+![Demo](https://raw.githubusercontent.com/wiki/reidha/checkbox_formfield/images/demo.gif)
+
+## Usage sample
+
+```
+class TaskEditPage extends StatelessWidget {
+  final _formKey = GlobalKey<FormState>();
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      appBar: AppBar(
+        title: Text(
+          'Sample',
+        ),
+      ),
+      body: Padding(
+        padding: EdgeInsets.all(16),
+        child: Column(
+          children: <Widget>[
+            Form(
+              key: _formKey,
+              child: Column(
+                children: <Widget>[
+                  CheckboxListTileFormField(
+                    title: Text('Check!'),
+                    onSaved: (bool value) {},
+                    validator: (bool value) {
+                      if (value) {
+                        return null;
+                      } else {
+                        return 'False!';
+                      }
+                    },
+                  ),
+                  CheckboxIconFormField(
+                    iconSize: 32,
+                    onSaved: (bool value) {},
+                  ),
+                  RaisedButton(
+                    onPressed: () {
+                      if (_formKey.currentState.validate()) {
+                        _formKey.currentState.save();
+                      }
+                    },
+                    child: Text('Submit'),
+                  ),
+                ],
+              ),
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+}
+```
+
+## Specifications
+
+### CheckboxListTileFormField
+
+|Parameter|Description|
+|----|----|
+|key|[FormField.key](https://api.flutter.dev/flutter/widgets/FormField/key.html)|
+|title|[CheckboxListTile.title](https://api.flutter.dev/flutter/material/CheckboxListTile/title.html)|
+|context|Provide a default color to `errorColor`|
+|onSaved|[FormField.onSaved](https://api.flutter.dev/flutter/widgets/FormField/onSaved.html)|
+|validator|[FormField.validator](https://api.flutter.dev/flutter/widgets/FormField/validator.html)|
+|initialValue|[FormField.initialValue](https://api.flutter.dev/flutter/widgets/FormField/initialValue.html)|
+|autovalidate|[FormField.autovalidate](https://api.flutter.dev/flutter/widgets/FormField/autovalidate.html)|
+|enabled|Whether the checkbox is enabled|
+|dense|[CheckboxListTile.dense](https://api.flutter.dev/flutter/material/CheckboxListTile/dense.html)|
+|errorColor|Color of error message<br> Default: `Theme.errorColor` (`context` is given), `Colors.red` (otherwise)|
+|activeColor|[CheckboxListTile.activeColor](https://api.flutter.dev/flutter/material/CheckboxListTile/activeColor.html)|
+|checkColor|[CheckboxListTile.checkColor](https://api.flutter.dev/flutter/material/CheckboxListTile/checkColor.html)|
+|controlAffinity|[CheckboxListTile.controlAffinity](https://api.flutter.dev/flutter/material/CheckboxListTile/controlAffinity.html)|
+|secondary|[CheckboxListTile.secondary](https://api.flutter.dev/flutter/material/CheckboxListTile/secondary.html)|
+
+### CheckboxIconFormField
+
+|Parameter|Description|
+|----|----|
+|key|[FormField.key](https://api.flutter.dev/flutter/widgets/FormField/key.html)|
+|context|Provide a default color to `errorColor`|
+|onSaved|[FormField.onSaved](https://api.flutter.dev/flutter/widgets/FormField/onSaved.html)|
+|initialValue|[FormField.initialValue](https://api.flutter.dev/flutter/widgets/FormField/initialValue.html)|
+|autovalidate|[FormField.autovalidate](https://api.flutter.dev/flutter/widgets/FormField/autovalidate.html)|
+|enabled|Whether the checkbox is enabled|
+|trueIcon|`IconData` if true <br> Default: `Icons.check`|
+|falseIcon|`IconData` if false <br> Default: `Icons.check_box_outline_blank`|
+|trueIconColor|`Color` if true <br> Default: `Theme.accentIconTheme.color` (if `context` is given), `Theme.iconTheme.color` (otherwise)|
+|falseIconColor|`Color` if false <br> Default: `Theme.iconTheme.color`|
+|disabledColor|`Color` if disabled <br> Default: `Theme.disabledColor`|
+|padding|`padding`<br> Default: 24.0|
+|iconSize|[Icon.size](https://api.flutter.dev/flutter/widgets/Icon/size.html)|