UpKeep works best in teams and requires an internet connection for you to be connected with your colleagues on the platform.
In short, UpKeep requires an internet connection whether that is via your cellular plan or via wifi.
We currently do not support an offline mode.
There are several reasons for this, but the first being that it causes a lot of sync issues across many different devices with multiple people all involved in the same company.
This may be something we include in a future, but not at this time!