Mobile services offering multi-feature query capabilities must meet tough response time requirements to gain customer acceptance. The top-k query model is a popular candidate to implement such services. We present a new algorithm SR-Combine that closely self-adapts to particular cost ratios in different environments optimizing both object accesses and query run-times. We perform a series of benchmarks to verify the superiority over existing approaches and use a psychologically founded model of response time requirements for mobile access. For a wide range of practical cases SR-Combine can already satisfy these goals. Where this isn’t yet the case, we show ways to get there systematically paving the way for real-time capabilities in mobile services.