What is a follower?
A follower reads readings already stored in Nightscout. The uploader supplies them. A caregiver phone, watch or home display can be a follower without owning the source sensor or changing treatment settings.
Keep the roles separate
Configure the uploader first and check fresh data in the browser. Then give the follower the site URL and the least access its documented workflow needs. Routine viewing should use a readable token, not the owner’s API Secret.
An app can have both upload and follow functions. Do not send followed readings back to the same site; that can duplicate data. Advanced remote-control features are separate from viewing and require deliberate version-specific configuration.
Check freshness
Compare a new reading and timestamp across the source, Nightscout and follower. A follower can display an old cached reading when its connection fails. If Nightscout is current but the follower is stale, troubleshoot the follower rather than recreating the source account.