Platinum Points earned through a smart device app are managed separately depending on the operating system of your device. If you use the app on an iOS device as well as an Android device, the number of Platinum Points you see within the application for each operating system will be different.
Platinum Points are awarded based on the operating system of the device used to complete a mission. There are also times where points will be awarded to the most recently accessed device.
The number of Platinum Points for each app that you see on the My Nintendo website is the total of these two, so please visit the My Nintendo website to view your total number of Platinum Points.