Thin plastic film-based CH3NH3PbI3-xClx perovskite solar cells were fabricated at low process temperature using a bilayer comprising an amorphous SnOx and mesoporous brookite TiO2 as electron collectors. Void-less high quality heterojunction structures achieve hysteresis-less photovoltaic performance with a power conversion efficiency as high as 13.4% and mechanical stability against cyclic bending.