From the list of features it seems to have a web-app, iOS native, android native, and you can host it yourself... What... what more do you really want? Also, what does "application" mean to you?
What do you mean? I looked through both, and they are both very easy to set up. Especially if you ignore the build documentations for wallabag which suggest OS level install of PHP, and do it with containers instead.
So, if you want to try it out, both are identical. 1. Clone, 2. docker-compose up.