I think you can use any Hardware/Device in as much it meets the following requirements.
The hardware requirements are quite acceptable. The Entry level Ubuntu smartphone needs to have at least a 1Ghz Cortex A9 (single core as the bare minimum), 512MB or 1GB memory, a 4-8GB eMMC + SD for storage, and Multi-touch capability.
The high-end Ubuntu "superphone" is a little more demanding and will need at least Quad-core A9 or Intel Atom processors, minimum 1GB for memory, minimum 32GB eMMC + SD for storage, and Multi-touch.*
I don't know if it support tablet because of screen resolution. it will be awesome though on tablet.
Sources: Click Here