  The integration of optoelectronic devices, such as transistors and
photodetectors (PDs), into wearables and textiles is of great interest for
applications such as healthcare and physiological monitoring. These require
flexible/wearable systems adaptable to body motions, thus materials conformable
to non-planar surfaces, and able to maintain performance under mechanical
distortions. Here, we prepare fibre PDs combining rolled graphene layers and
photoactive perovskites. Conductive fibres ($\sim$500$\Omega$/cm) are made by
rolling single layer graphene (SLG) around silica fibres, followed by
deposition of a dielectric layer (Al$_{2}$O$_{3}$ and parylene C), another
rolled SLG as channel, and perovskite as photoactive component. The resulting
gate-tunable PDs have response time$\sim$5ms, with an external
responsivity$\sim$22kA/W at 488nm for 1V bias. The external responsivity is two
orders of magnitude higher and the response time one order of magnitude faster
than state-of-the-art wearable fibre based PDs. Under bending at 4mm radius, up
to$\sim$80\% photocurrent is maintained. Washability tests show$\sim$72\% of
initial photocurrent after 30 cycles, promising for wearable applications.
