Comrade's Jen Kuo presents her usability findings from a recent biometrics study.

1. Biometrics Usability Lessons
(that we learned from some real talk with real people)
5

2. 2 5 Biometrics Usability Lessons
PUTTING BIOMETRICS TO THE TEST
More and more apps are adopting fingerprint authentications as a
way to differentiate themselves or to project an image of
innovation and security.
Still, many decision-makers worry about adding biometrics. They're
concerned users will get confused or think it’s unsecure, or they
figure the process is just a trend that’s more trouble than it's worth.
And if they do decide to implement it, little best practice is
available.
If you're considering implementing biometrics, instincts are great,
but it's best to have the facts. That's why we’re sharing our findings
from a fingerprint authentication usability study we performed to
understand how users react to this new technology.
Is it easy? Is it secure?
Here's what we learned.

3. 1
Users registering their fingerprints had a different
experience whether they were using an Apple or an
Android device.
NOT ALL DEVICES ARE
CREATED EQUAL
Be aware that experiences between devices are not
the same and there are differences between Software
Development Kits. Unlike Apple devices, Android
devices allow users to add their fingerprint as part of
the registration process, which provided a more
seamless experience for the user.
Recommendation

4. 2
Once their fingerprint was registered to their device,
users thought they were done with the process and
didn't know they also had to enable it in their
application.
LET THE SUN SHINE IN
Make sure the experience between adding a
fingerprint and enabling it to your app is clear. Once a
user registers a fingerprint on the phone and logs
back in, give a prompt to actually take the step to
enable the fingerprint in your app's settings. Keep it
top of mind and people will follow through.
Recommendation

5. 3
Once they started thinking about it, users were
curious (and a little concerned) about where their
fingerprint was actually going to be stored. Is it on the
device? With the application? With the OS? If they
lost their phone, who would they call about their
fingerprint—Verizon? Apple? You?
FACE THE FACTS ABOUT
SECURITY
It's easy to get out in front of the question. Provide a
short explanation or an infographic to explain where
fingerprints will be stored. Don't just say, "It's secure!
We promise!" with no explanation of why. Here's an
example of what you can say: "When you add your
fingerprint to your phone, it stays on your phone. We
don't keep a copy of it.” Users will feel more
comfortable using the app if their security concerns
are addressed proactively.
Recommendation

6. 4
A participant who had recently gotten into an
accident and only had use of one hand was skeptical
about the process.
DON’T FORGET EDGE
CASES
From guitar players with callused fingers to people
with missing limbs to those with limited mobility and
beyond, there are a lot of people who won't be able
to use their fingerprint to authenticate, whether it’s a
temporary or a permanent condition.
Always offer an alternate solution—it's just an
accessibility best practice. Make sure users can
easily choose between authenticating with or without
a fingerprint.
Recommendation

7. 5
In some cases, users wanted to use multiple
fingerprints to authenticate and they also wondered if
it was possible to add another user’s fingerprint to
authenticate with the same device.
REMEMBER THAT
SHARING IS CARING
People, especially spouses and families, share their
devices, in particular iPads. Since it's possible to use
multiple fingerprints to authenticate on these devices,
your app should definitely do the same. Users like
consistency, especially when it’s offered as part of the
device setup process.
Recommendation

8. 8 5 Biometrics Usability Lessons
SO WHAT NOW?
In the end, we realized that biometrics are here to stay.
People encounter them, figure them out, like them, use
them, and they get on with their lives. We were honestly
surprised that every single participant said he or she would
happily use fingerprints to authenticate their devices. That
seems to be a pretty clear indicator that biometrics are the
way to go.
All you have to do is give your users a little bit of guidance
and clarity about security. And you need make sure your
app functions exactly the same ways different devices
actually treat fingerprints. Which, when you think about it,
is pretty easy—just like logging in with your fingerprint is
really easy.
“Don’t knock it until you’ve tried it. Just give it a try. I think
you’d honestly be missing out if you didn’t do it.” – J. Kuo

9. 9 5 Biometrics Usability Lessons
THANK YOU
Jenn has been creating online and mobile experiences for the past seven years. She
started her career as a visual designer for mobile gaming startups in Las Vegas and
the San Francisco Bay Area, and has successfully published over 20 mobile and web
applications.
Often the sole designer on projects that did not include a user experience resource,
Jenn initially addressed UX out of necessity, but changed tacks with her career once
she discovered her passion for creating better interactions.
At Comrade, Jenn has focused her user-experience efforts across platforms, from
redesigning the online banking experience for Bank of the West and also launching
their mobile application experience, to creating responsive online financial calculator
tools for Leadfusion. Jenn’s user-centered design solutions promote ease of use and
employ best-in-class interaction design paradigms.
Jenn holds a BA in Psychology from the University of San Diego, and a BFA from the
Academy of Arts University.
JENN KUO
User Experience Strategist
jenn@comradeagency.com
510.277.3400
www.comradeagency.com