[smt88]

Why not have a physical button? Several companies have released programmable buttons.

You could also have an emergency-only prepaid cell phone and only give the number to those people.

There's also the traditional Life Alert type options that would summon first responders.

[esac]

physical buttons are hard to debug! emergency-only cellphone looks like the better alternative for now even if it would require me to use two phones or swap sims. It's not a life risk situation, more a (business and peace of mind) life risk situation so i don't think ~life alert could work

[smt88]

I forgot that definitely Android and probably iOS allow you to make exceptions to do-not-disturb mode for some contacts. Would that do it?

[matt_the_bass]

Take a look at particle.io. They have a super simple button that you can connect via WiFi or GSM to ifttt or twilio really easily. Sample code leaves almost nothing to debug.