WATERLOGGED

Free (with in-app purchases), waterlogged.com

This hydration monitor makes it easy to track your water intake day-today, and see if your drinking is on point over time. You can set targets for daily H2O, and assign your own bottles and glass sizes to make it easier to record. But most usefully of all, it’ll remind you if you’ve left that full water bottle on your desk but forgotten to drink it. It also plays nice with Apple Health, MyFitnessPal and Fitbit.