Android app obligatoire pour une population spécifique, sur un matériel spécifique

Hi yohan_g, 

I cannot read french so I had to translate your question to english, so i hope you can understand my answer. 

As i understand from your question is that you want to assign an application to a user group and that the application only will be installed on an android tablet. 

In my opinion you have 3 options

1) 1 static group with the android tablet which will be used by the users and assign static group to the app

Create a basic group and add members - Azure Active Directory | Microsoft Docs

2) create a dynamic device group for android tablets. Assign the dynamic group to the app

Rules for dynamically populated groups membership - Azure AD | Microsoft Docs

3) Create a user group who need the app installed, create a filter, and set the filter on the user group assignment. 
Create filters in Microsoft Intune | Microsoft Docs

I hope this will help you, and please let me know if you have more questions.

If this fix your problem, please mark my answer as the solution.

With kind regards,

Rene