This seems to be well built for a 1st Android App. 2 things I feel could be improved though : - The concept of logging to develop healthy habits should be emphasized, or completed with some kind of planning instead of only logging - The design, even if not bad because it uses native elements, lack some kind of personal touch

Thanks for the feedback! We are split on whether we should exclusive make it a habit-building app. Lots of people use the app just for logging. Goal setting would definitely make it more useful - we have to figure out how to implement it without forcing it on people who don't need it. And yes, the design needs work :)