Inner links
The hierarchy between categories and events are intentionally narrow, it would be relatively easy to generalize the concept of categories and allow having subcategories. That goes against the short interactions and the frustration-driven design principles.
The app was first developed using a server, and when that was the case, I had some events linked to the URL of a category. For example, there are ruminations that could be associated with Acceptance or Defusion, so registering them would open the category of exercises related with the associated skill. That was very useful.
In order to allow this without enforcing it, the possibility of copying the URL of a category will be introduced to copy it as the action of an event. The category of the triggering event can be understood as a evaluation category, while the target category can be understood as an action category.
To keep this virtual hierarchy of categories shallow, and enforcing the view of evaluation vs. action categories, it won’t be possible to trigger an action that leads to a category two times in a row.
Questionnaires
Another feature that was included in the server version, but not in the local first version, is a section to complete psychological questionnaires. Technically is not far from being finished, and a way to include questionnaire translations was also introduced while migrating to the local database structure, but some research is required to respect the intellectual property of the questionnaires that were selected originally.
Creating questionnaires from the app is more complex and it won’t be added in a near future version unless someone will come from heaven and do it.
Sharing
The local database version was created using a software library that allows synchronizing information with a server or a peer. To transform uMetric from being a single-user tool to a cooperative effort, the information structure was designed to allow secure sharing of subsets of the data stored with a particular person. For example, you can decide to share with a person the responses of one questionnaire, but not the event logs, or the responses from the rest of the questionnaires.
In order to achieve this, we first need to establish a relationship of trust using a server or directly with another person in the same local network, and acknowledge their identity. This way, we know the user identifier and a cryptographic signature we can use to encrypt information in a way that only that person will be able to read it.
If a server is used, the information contained in the server will be the identifier of the recipient and the encrypted information. Storing our information in the server is just a particular case of this scheme.