Hi @Blitheringeejit
if your question is about accessing Install ID in a form you can't do that for now. We added Install ID recently because we will be forced to get rid of Device ID so then we will use that new Install ID instead. More info: Collect will need to stop using IMEI as deviceID and making simSerial and subscriberID available
If I'm wrong and you have your own fork and need to change something the code responsible for that id is in SharedPreferencesInstallIDProvider class.