The consensus opinion of professional reviews is that the 5s is superior. The Nexus beats the 5s on display but lags the 5s in battery life, camera and build quality. CPU/GPU are comparable. We could continue to list minor features in each phones favor all day but those are the major specs most people care about. If you look at reviews across the board the 5s is a better reviewed phone and the Nexus 5 receives marks around the 5c. Vs the 5c it wins on display and CPU/GPU but loses on battery life, camera and build. It may be better than the 5c but I think it's a closer comparison.