Navigate to Text property of BAtxtinput field and type Host.BrowserAgent as value.
Navigate to Text property of OSTypetxtinput field and type Host.OSType as value.
Navigate to Text property of SessionIDtxtinput field and type Host.SessionID as value.
Navigate to Text property of TenantIDtxtInput field and type Host.TenantID as value.
This way we learnt to use host objects in Canvas App.