2009: Openmoko Freerunner
2010: N900
2012: N9
2015: N9 + N900
2016: N9 + N900 + Nokia 808 Pureview
2018: Droid 4 + N9 + Nokia 808 Pureview + N900

Yes I carry these with me at the same time.
Usually N9+Droid4 in my pocket, 808+N900 in my Bag.

The purposes:
Droid 4: Signal, Android Apps I can't avoid, Browsing
N9: Reading, Music, Movies, Stargazing, Reddit, Mail
808: Taking Pictures and Videos, Audiobooks
N900: nowadays only SSH and VNC to other devices.

I would gladly take a device which fuses some of the functions.
The FxTec Pro 1 has a chance.