u/Spirited_North3077

I run a pretty basic app called Zeopoxa on my cell phone to monitor my rides, and I back it up with a Cateye Velo 7 computer. The app always reports about half a kilometer shorter and a minute longer over a 45 km ride. The Cateye is calibrated accurately, I believe. Any similar experiences? Beside inaccuracies in the wheel size on the computer, what else might cause it?