The m.Care application is secure, but we highly recommend you use a non-trivial pass code for opening your phone, or your finger print or face data if available on your device. This will help protect you in the event your device is lost or stolen.
m.Care also recommends turning on the iOS "Find my" application to help you locate a lost device. If your device is lost, you can use iCloud to disable the device so that it can not be used when found.