What if your phone has no service at the time of text?
What if you forget and your leave your phone in a different room?
I suppose it all comes down to how your emergency contact choose to handle the situation. It's not as if it automatically calls 911 (unless that's what you make you emerg. contact?
> "Are you okay? (Please reply yes or no)"
> Kidnapper hears phone vibrate... reads text... responds "yes".
Without Kitestring, emergency isn't contacted.
With Kitestring, emergency isn't contacted in your particular situation, but might be if you fell when hiking or somehow got yourself electrocuted, or were caught in a rip while swimming, etc. Or if you had a PIN lock on your phone.
Luckily, security agencies have already solved this particular problem.
Instead of texting "Are you okay, please respond [this way]", there's a very simple challenge-response mechanism.
Agent in the field knows the correct response and a duress response to literally any pre-shared question ("How many eggs do you need to make an omelette?" Correct answer: "I'd rather have waffles", duress answer: "three").
All of the "what if [technical fault, stupidity]" is solved by escalation. Replace a text with a phone call in two minutes. Then call an emergency contact in 5. Then call the police in 10. (Adjust numbers to your locale and situational urgency).
When the time is up, you have to put a PIN in to give it the okay. There's a duress PIN, so even in the scenario where a kidnapper forces you to disable the app, it still achieves its goal. The alert is triggered from the server, so even if they smash your phone it still works (albeit without any more location tracking, obviously).
There's ways to handle most worst case scenarios, so long as you accept the possibility of false positives.
> "Are you okay? (Please reply yes or no)"
Kidnapper hears phone vibrate... reads text... responds "yes".
What if your phone has no service at the time of text?
What if you forget and your leave your phone in a different room?
I suppose it all comes down to how your emergency contact choose to handle the situation. It's not as if it automatically calls 911 (unless that's what you make you emerg. contact?