Yes, internet access is required for the Safeture Mobile Application to work as intended. However, the app keeps all previously viewed information locally on your phone and it will be available while offline. Some communication can still occur via SMS. You will of course still be able to receive SMS from the Safeture platform without internet access.
When offline, your latest location sent to the servers will be shown in the Web Portal, but no updates will be sent until the app goes online again.