Device and browser signals
Which phone, which browser, and which screen size you used to access; this helps identify where problems occur, and where loading stalls for Android users
Location-based, only a general city-level concept is kept, comparing experiences of users entering from Dhaka, Chattogram, or Khulna to identify issues
Session and cookie-based data
Cookie-policy-based language preference, login status and navigation path may be stored to help account security and fast loading
Even if multiple tabs are opened, the session does not become unstable, so you don't have to repeat the same steps