Basically, I am looking for an Android app that every day (or possibly in other intervals) offers me the option to "check", that I did something, like for instance taking medication. This is because I sometimes forget, whether I actually did something important or not, especially if it is easy to do. At a later time, I should then be able to look at something like a calendar, which shows the days I did said task.
It would be great if the app could handle multiple tasks simultaneously. Another useful but not necessary feature would be specifying how much I did something (like how often or for how long) and displaying statistics for this task.