Walk, walk, walk!!! Measure through Walk.
1. The best accuracy because of new algorithm with Apple Co-processor;
2. The iPhone can be sleep when it is measuring;
3. Can pause the measuring in long way measurement;
4. Share data via message, email and etc.;
5. The data from Apple Watch can be managed by iPhone.
Notice: The App runs on iPhone 6 and iPhone 6 plus only because it requires the "Motion & Fitness" capability.