My partner introduced me to the Dutch "112" app (112 is the emergency telephone number in Europe).
I hope I never need it of course, but if I do it automatically shares my location and it allows me to chat instead of call if I would be in a situation that requires that.
Also, I really enjoy Jepster as my biking computer when cycling. The guy that built it is also very approachable when you find a problem, which is great.
And when you're planning to get kids have a look at "Kinder"...