The app may not be available in other countries. I have it and the idea is that I turn to choose it on before I walk through a dark alley, and I put my thumb on it, and if anyone messes with me and this my thumb comes off, help is notified. It's not a constant tracking, and I do it for myself. I turn it on for 2-3 minutes maybe once or twice a week. No one is notified of my location unless my thumb comes off and I don't put into the code for that short period of time re on.
I carry mace too, but it's my choice. If I suggested to a friend or family member that I would like them to carry mace or any other safety device, and they said that they didn't want to, and they are an adult… that's up to them. I can advocate, but I can't make them do it.
You are also totally allowed to change your mind at any point in time. You can try it for a bit, and if it's just not your thing, that's OK. You can try not doing it for a bit and then if you change your mind and want to do it that's OK too.
Your judgment is more sound then it may feel like, and at the end of the day, it is your call. I think that's the most important thing. Not so much as to whether or not you use this or that safety device, but that you know you do have the freedom to say no, and pick and choose what you do and do not want to do.