Question about Emporia Smart 4

Good day, we have some questions about this as we want to make sure it is a right fit for my father: 1) Is it really like it looks in the pictures that you can call 911, family/relatives and friends very easily? 2) What about the volume? Can it be set loud enough for people with hearing aids or without hearing aids. Is the volume then annoyingly loud e.g. in Aldi? It would be ideal if it didn't have to be changed (sometimes louder, sometimes softer), because the re-setting would be forgotten. On the other hand, everyone then hears a ringing, only.... 3) Are the icons or apps all actually nice and big so that they are easy to read (with the glasses)? 4) Are the apps easy to use? Everything looks perfectly simple in the pictures, we would like to see that when setting up. 5) Can WA or other communication apps be installed, or can all apps for Android be installed, and is it possible to deny the installation of apps by means of a password or something like that? The aim is to allow as much freedom as possible, but to prevent all problems in everyday life in advance, to let them be reduced independently (here: by the mobile device) or to let us solve them. We are very, very grateful for helpful answers of any kind! All the best.