A team that call themselves “SailPi” has ported the SailfishOS to the Raspberry Pi. Using it, they’ve put together a DIY touchscreen tablet using the Raspberry Pi’s DSI screen. They’ve then made it portable by using a 20000mAh powerbank and a wifi dongle. It’s a bit precarious, but it’s a lovely proof-of-concept. You can download the portrait-orientation OS image from their blog and read more here.