docs: update the README (#772)

README.md

@@ -12,12 +12,12 @@
 [![popularity](https://img.shields.io/pub/popularity/openfoodfacts?logo=dart)](https://pub.dev/packages/openfoodfacts/score)
 [![pub points](https://img.shields.io/pub/points/openfoodfacts?logo=dart)](https://pub.dev/packages/openfoodfacts/score)
 
-Dart package for the [Open Food Facts](https://world.openfoodfacts.org/) API. Free and Easy access to more than 2.7 million food products information from all around the world.
+Dart package for the [Open Food Facts](https://world.openfoodfacts.org/) API. Free and Easy access to more than 2.9 million food products information from all around the world.
 Open Food Facts is powered by contributors from around the world and is constantly growing thanks to them.
 
 ## General principles, how does it work ?
 
-We use the ability of the Open Food Facts API to return products results in Json, we then generate easily understandable objects structures to make it simple for you to use.
+We use the ability of the Open Food Facts API to return products results in JSON, we then generate easily understandable objects structures to make it simple for you to use.
 
 This plugin also allows you to edit a product or upload a new one to Open Food Facts. Using the same simple product structure you can create a product object or edit an existing one and send it to the API using a single function.
 
@@ -216,11 +216,11 @@ dart test
 
 ### Official application
 
-**Smoothie** is the official developed by Open Food Facts, which will soon be released on Android and iOS. The source code is also available on [GitHub](https://github.com/openfoodfacts/smooth-app).
+Open Food Facts (Codename **Smoothie**) is the official app developed by Open Food Facts, which is available on [Android](https://play.google.com/store/apps/details?id=org.openfoodfacts.scanner) and [iOS](https://apps.apple.com/app/open-food-facts/id588797948). The source code is also available on [GitHub](https://github.com/openfoodfacts/smooth-app).
 
 ### Third party applications
 
-Feel free to open a PR to add your application in this list.
+Feel [free to open a PR to add your application in this list](https://github.com/openfoodfacts/openfoodfacts-dart/edit/master/README.md).
 
 - **Glutten Scan**. [Android](https://play.google.com/store/apps/details?id=com.healthyfood.gluten_free_app) / [iOS](https://apps.apple.com/ch/app/gluten-scanner/id1540660083)
 - **Halal & Healthy**. [Android](https://play.google.com/store/apps/details?id=com.TagIn.Tech.handh) / [iOS](https://apps.apple.com/ch/app/halal-healthy/id1603051382)