top of page

Reframing verification experience


In this project, I conducted the research and redesigned a feature of a widely used mobile app to improve the experience of the user identification process. Users can complete the process intuitively and efficiently through the new behavior-based CAPTCHA while maintaining high security at the same time.


Desk Research

Contextual inquiry

Usability Testing

UX Design


Oct 2016 - Dec 2016


"A CAPTCHA (an acronym for "Completely Automated Public Turing test to tell Computers and Humans Apart") is a type of challenge-response test used in computing to determine whether or not the user is human. This user identification procedure has received many criticisms, especially from disabled people, but also from other people who feel that their everyday work is slowed down by distorted words that are difficult to read. It takes the average person approximately 10 seconds to solve a typical CAPTCHA." 

                                                                                                                                                   -- Wikipedia


CAPTACHAs are used almost everywhere to prevent malicious registration, spam, and other malicious behaviors. It is necessary to have the identification procedure when the malicious activities exist.

So, how to reduce the burden on users?

In order to answer the answer, I try to understand the usability of the current used CAPTCHAs, to figure out how to better the user experience when people are recognizing and inputting them.

So I started the research...


I experienced the CAPTCHAs on websites and mobile APPs by myself.


And developed the user experience report document.

I observed how do people operate in the identification procedure and how do they feel during the process.


By referring relevant literature information of the usability of CAPTCHA, I found the factors which influenced the user experience:


I summarized the classification of CAPTCHAs and their usability.


Experience Optimization

Experience Optimization

Based on my research results, I decided to choose the CAPTCHA of the mobile APP "12306" -- the ticket order APP of China, which has a great number of active users and is critiqued by users for a long time due to its troublesome user identification procedure, to make its user experience better.

What are the difficulties?

In order to improve user experience of the CAPTCHA in the ticket order procedure and ensure the security to avoid the malicious ticket order behavious, I observed and interviewed the users of "12306" ticket order APP, and found that:

Current ticket order process:
  • Who are the users 
    Across a broader age spectrum, with different backgrounds.

  • How long does the process cost? 
    6-20 seconds.
    Text recognition costs 1-2 seconds, recognition of some images took 5-18 seconds.

  • How is the accuracy? 
    About 50%.

  • How do the users feel? 
    Frustrated and upset

How do I design a better method to accomplish the user identificaton procedure?

Considering the character of user and CAPTCHA, the new CAPTCHA should balance the security and user experience. It should be :


The new CAPTCHA I designed: 

  • is based on users' behaviors, it is convenient for user to recognize and operate;

  • utilizes the information which is hard for computers to recognize and identify, ensuring the security;

  • combines the identification procedure with the information confirmation behaviour, helping users accomplish the necessary information confirmation step while confirm their identities;

  • reduces the operational burdens and helps users avoid mistakes at the same time, improving the ticket order efficiency.


Before the user identification procedure, users choose their desired tickets.


The CAPTCHA utilizes the departure time, origin station and terminal for users to review they tickets and for the machine to identify users' operation at the same time.



It was a great opportunity to be able to keep learning while researching and designing the CAPTCHA. I learned a lot during the process:

  • Never ignore the context, it matters a lot.

  • There is always a better plan to improve the experience even under technical limitations.

  • See a bigger picture and some problems can be felicitously solved at the same time.

bottom of page