• Neuen Kontakt hinzufügen
  • Nachricht verschicken auf den Wegen:
    • Unsicher
    • Verschlüsselt
    • Authentifiziert


  • Jedes Mitglied der Gruppe macht die Analyse für die Themenfelder der Gruppe (s.o.) selber (= keine Zusammenarbeit), da jede Person andere Fehler findet, sodass sich die Analysen ergänzen.
  • Bitte so dokumentieren, dass die Analyse und ihre Ergebnisse dem Lehrenden (Jan) und dem ChatSecure Team verständlich sind. Schreibt auf Englisch (wenn möglich, sonst Deutsch) und nutzt Screenshots oder Skizzen.


Heuristic analysis for ChatSecure

1. Visibility of system status

  • Sending messages: The lock kept open, when I clicked on “start OTR”, so it didn`t work and I don`t even know why. (Description box needed!)Later I realized it will only work if the chat partner is online. I would like to send a secure message to an offline person, but don`t know how. Need I download the OTR Keystore then? This friend also didn`t receive my messages at all and I didn`t know that, because no error sign occurred. (See “error prevention”)
  • Add contacts: When I added a contact, he showed up in the contact list twice. I deleted one of them… later “both” accounts were gone, so I fully deleted the contact by accident.


2. Match between system and the real world

  • Sending messages: I have no knowledge in computer science, so I would like to have a little explanation about what OTR or this OTR Keystore is. I would like to read easier words, like “start secure messaging” that don`t make me wonder what I am doing. Furthermore, I only found the “import OTR keystore”-button just by accident!
  • Add contacts: No problem.

3. User control and freedom

  • Sending messages: All ok.
  • Add contacts: All ok.

4. Consistency and standards

  • Sending messages: No problems.
  • Add contacts: The touch screen doesn`t work sometimes, when clicking on “Add a contact”.

5. Error prevention

  • Sending messages: I didn’t know my messages weren’t sent at all. My message window was all empty. I couldn`t see that I did not send my friend something nor could I see her messages.
  • Add contacts: I didn`t know, it would delete the “right” account, too.

6. Recognition rather than recall

  • Sending messages: Didn`t understand the box that plopped out, when I wanted to import the OTR keystore. (And don`t know what it is for, by the way.) It was only open for a few seconds, so I couldn`t read all of it. After I read it 3 times, I still didn`t found this file, the window wanted to lead me to.


  • Add contacts: After typing in the name in the contact box, I wanted to click on “invite”. For that I clicked in the red box below, because I intuitively thought, I would come to the interface before. Maybe it is better to place the “invite”-button somewhere in the red box, because you won`t have to click the keypad away then.


the "invite" button is unseen


the interface before

7. Flexibility and efficiency of use

  • Sending messages: No problem.
  • Add contacts: Everything ok.

8. Aesthetic and minimalist design

  • Sending messages: I clicked on someone on the contact-list. The message window opened and I typed something. So now, to write another person, I needed to slide over many people before I got to the “general” contact list, where all friends are listed. I think having the general list in one slide is way easier.


The “general” contact list

  • Add contacts: Is ok.

9. Help users recognize, diagnose, and recover from errors

  • Sending messages: See points 1 and 5.
  • Add contacts: See points 1 and 5.

10. Help and documentation

  • Sending messages: As said before, I would like to have some explanation what an OTR is. Or just easier words and an extra field for “how it functions” in the settings.
  • Add contacts: Everything ok.

Rework of the older paper-prototyp