PeeWee is simplistic minimalist offline password saver.
The app is digitized alternative to pin codes and passwords written on paper in your wallet next to your credit card and also as way to store passwords offline in your phone and not send it to 3rd party for "safekeeping".
As long as you are not target of some specialized secret agency that would secretly steal and reverse-engineered your phone software, your grandma's favorite social network passwords or your mom's mail logins are encrypted and data can't should not be accessible outside of apps.
App maximally aims at simple to use experience, so even my grandpa can use it. Due that It relies on basic common sense in security measures for your phone, e.g. setting up lockscreen on your phone, not using rooting devices, installing only safe apps from secured sources etc.
