This is a very easy to use app that allows you to write notes, by storing them in local textual files, one for each day of your life and by protecting them by password.

Well, but it is not only this, or better, its goal is completely a different one.

Let's introduce the scenario where this app can live:

Assume you have a relation with a person that acts on you with some sort of undesired authority, and, for this, he (or she) persuaded you not to apply a lock on your smartphone, for instance "because there is no need to do this, since ....we are good people ...". Assume, at this point that you suspect, as opposite of what declared, that you smartphone is handled frequently by this person and you would like to collect some evidence of that. Well, this app has been been mainly designed to give this kind of help to the owner of the smartphone.

For that it is composed by two completely different behaviors: a "declared" one, that is the Diary protected by password, and the "substantially primary" one, that, through a completely secret session, allows the owner of the smartphone to start monitoring each physical movement of the device (movement obviously interesting only when the owner leaves its device), by collecting the date-time of each start of motion and of the respective end of motion, letting, indeed, the owner quantify the frequency and the duration of each period of time in which the "intruder" handles the smartphone. Note that the existence of the secret session should be completely ignored by the intruder, that, even with some tech knowledge, could suspect at most some indexing background activity.