I have several existing surveys that are set to Public for submissions, so that users do not need to sign in to download the survey. Instead, I tell them to visit the survey link in a browser on the device (e.g. arcg.is/xxxx) to access and download the surveys. I have found (on iPhone, iPad, and Android devices) that when I release updated versions of the survey, if the users do not delete the existing copy on their devices, the updated version will not overwrite the older version. So when they go to use the "updated" version, it's actually the same old one. Only by deleting the survey entirely and redownloading it do they get the updates, which also deletes their sent and draft surveys. This is a problem, since most of them want to retain their "Sent" data locally. Is there a setting I have missed, or is this just a function of the public survey option?