In absolute terms it's not stable, in relative terms it can be. If you gave me the choice between storing my money in Bitcoin or Turkish Lira I would choose Bitcoin every time. If I have the option to use USD instead the answer is different.

> helps people without access to banking but with a stable, constant internet connection and perfect operational security

You don't need constant internet connection unless you are mining or want to verify a payment right now. And mobile internet and smartphones are surprisingly prevalent in the third world (and among homeless in the first world).