Project architecture

I have to create app and which has three main module (client, admin, mobile app of client).
which architecture i have to used? I mean create a separate app for all the three modules or create only one app which contains all the three module.

I don’t want to give access of admin module into mobile app is there any provision for that?

I have created a app which has two different login form one for admin and another for client, in mobile by default it opens a login page of admin and i want to open login page of client. So, How can i set default page for mobile app?

Hi,
try this package : https://atmospherejs.com/mystor/device-detection