Service Designer (Interaction/Mobile Focus)Location: London/Remote Rate: £700 per day (Inside IR35) Clearance: Must be eligible for BPSS and SC (active SC highly desirable) Contract Length: 12 months Start Date: 06 July 2026Sanderson Government andamp; Defence is supporting a public sector organisation to secure an experienced Service Designer to work on complex, user-centred digital services.This role will suit a designer with a strong interaction and mobile design background, comfortable working across end-to-end services within multidisciplinary agile teams.The roleYou will be responsible for designing clear, accessible and inclusive service interactions, with a particular focus on mobile-first experiences across iOS and Android. Working closely with service designers, researchers, developers and product teams, you''ll help shape user journeys and design decisions from discovery through to live.Key responsibilitiesDesign clear, accessible, user-centred interaction flows across complex end-to-end servicesCreate mobile-first experiences across iOS and Android platformsCollaborate with service designers, researchers, developers and product teams within agile delivery teamsMobile prototypingProduce high-fidelity interactive mobile prototypes illustrating interactions, gestures, transitions and system behavioursUse prototyping tools and lightweight code to simulate complex user flowsSupport usability testing, technical feasibility discussions and collaboration with engineering