+1 for updated browser ( possibly better webgl support on aquaris 4.5)
+1 for nextcloud/owncloud sync of calendar and contacts)
aethercast for aquaris 4.5 ( also possible in future OTA)

@doniks
http://blog.bhdouglass.com/openstore/ubuntu-touch/2018/05/10/openstore-xenial-support.html

while pdf files should already work, it was not yet possible to build a docviewer packages with libreoffice support.
I wanted to post the steps I already did and the results