As far as the app library thing is concerned, I think that depends on the distro and if there are special requirements for the apps it runs. However, if it can just simply run Linux packages with a touchscreen interface, then I already mostly migrated to multiplatform foss apps that I can export my settings to.

However I really don't want to buy a new phone anytime soon. I was planning for this one to last me atleast 5 years.