An organization called "Senior Helpers" recommended VitalLink, which is based near where we live. (We had a representative from Senior Helps come out and do an evaluation to see if their services were a good fit, and the rep thought we she get a medical alert system since my mother lives alone.) My sister noticed that another company Alert1, also has a "mobile" option (which VitalLink does not), that she thinks could be helpful, as it works outside the home.
I can't seem to find any actual reviews, as the "review" websites I have found are clearly bogus and sponsored by the company itself.
The other problem I have is that this is for someone with dementia, who is not really capable of learning a new system. Will she even remember to press the "panic button" if she falls or needs help?