Skip to main content
No items found.
logo dropboxsign
Why Dropbox Sign?
Expand or collapse accordion

What you can do

Sign documents online
Create electronic signatures
Choose or create templates
Fill and sign PDFs
Complete online contracts
Document management
Explore features
icon arrow right

Use cases

Sales and business development
Human resources
Startups
Financial technology
Real estate
On-demand services
Products
Expand or collapse accordion
icon dropbox
Sign
Make it easy to send and sign
icon dropbox
Sign API
Integrate eSign in your workflow
icon dropbox fax
Fax
Send faxes without a fax machine
icon dropbox integrations
Integrations
We meet you where you work
Resources
Expand or collapse accordion
Blog
Workflow expertise & product news
Customer stories
Real-world stories with real results
Help center
In-depth guidance for our products
Resource library
Reports, videos, and info sheets
Developers
Pricing
Expand or collapse accordion
Dropbox Sign pricing
Find the right plan for you
Dropbox Sign API pricing
Real-world stories with real results
Contact sales
Sign up
Contact Sales
Sign in
Expand or collapse accordion
Dropbox Sign
Dropbox Forms
Dropbox Fax
Free trial
Blog
/
Developers

Developer Spotlight: Meet our inaugural Go Paperless Hackathon Grand Prize winner Arnold Rozon

by 
Rosie Cunningham
February 21, 2023
3
minute read
CoSign main screens
icon tooltip

New look, same great product! HelloSign is now Dropbox Sign.

icon close

Arnold Rozon is our 2022 hackathon Grand Prize winner!  His native iOS application CoSign uses near-field communication(NFC) to distribute eSignature requests and biometrics so people can sign documents with their iPhone Face ID. Check out his full submission.

‍

The makings of a hackathon winner

Getting his first taste for development while working as a designer, Arnold was fascinated and subsequently taught himself to code in his brother’s Chicago basement in just eight months. From there, he’s worked for big Chicago-based tech companies and San Francisco-based fintech startups.


As Arnold progressed in his development career, he found himself gravitating toward mobile development. “I realized I'd become really bored with traditional web programming, so I started learning Swift and iOS development in my own time.”


Eager to hone his new mobile development skills on real-world projects, Arnold turned to hackathons on Devpost and found the Dropbox Sign API Go Paperless Hackathon.

Go Paperless Hackathon Grand Prize winner Arnold Rozon
Go Paperless Hackathon Grand Prize winner Arnold Rozon


The experimental path of a winning hackathon eSignature app

Designed and built in under seven days, Arnold’s winning hackathon idea, CoSign, lets people sign documents with biometrics and send signature requests through NFC tags.

‍

Arnold credits the quality of the documentation and the ease of development as the reason he could create a winning hackathon project so fast. “The Dropbox Sign API has really good GitHub documentation. Anytime I needed a method to get information from Dropbox Sign, it was documented and there was an example in the documentation showing me how to use the method and what you could expect as a response. That saved me so much time as a developer.”


To build the biometric element of CoSign, Arnold combined the Dropbox Sign API with iOS Face ID. “I used in-browser JavaScript to select all elements on the Dropbox Sign Signature request.”


Building the Face ID feature into the app wasn’t as straightforward as it seemed, as a conflict between the Sign API and iOS default authentication methods became a blocking issue.


The iOS default authentication for Google single sign-on was OAuth WebView, and this piece was a requirement for the Face ID functionality. However, OAuth WebView wouldn’t support Arnold injecting the code needed to authenticate the signer with Dropbox Sign. Without being able to authenticate the signers, it was impossible to complete signature requests.


Knowing he couldn’t authenticate with WebView, Arnold looked for alternatives. “I realized you can authenticate with Dropbox via a regular web view. So when I press the signature request in CoSign, it opens up the signature request in a normal web view where I can authenticate with Dropbox, and then I have access to the signature request.”


With his workaround in place, Arnold’s Face ID function was operational.


Then when Arnold saw petitioners collecting signatures outside his local Target, inspiration struck for a way to add even more value to his winning hackathon submission. “I started thinking about all the better ways to share information and signature requests that would be easier for someone who's out and about or might be dealing with a large number of people.”


The solution he landed on was NFC tags. By putting a phone near an NFC tag, people would have an easy and contactless way to share information. And by incorporating the Dropbox Sign API signature request function into the process, people could request signatures and sign documents, like petitions, too.

‍

CoSign systems diagram
Cosign systems diagram


What’s next for Arnold?

“I think we are at a crucial juncture when it comes to software. The ideas of the past 10 years have become extremely saturated. There are a lot of new paths that we can take as builders. I'm just trying to put myself at the forefront of whatever is coming next. I've recently been exploring content creation, a little bit of blockchain, and I’m trying to learn more about machine learning.”


Congrats again to Arnold. We can’t wait to see what else you build!

Stay in the loop

Done! Please check your inbox.

Thank you!
Thank you for subscribing!

Lorem ipsum

Lorem ipsum dolor sit amet, consectetur adipiscing elit. Suspendisse varius enim in eros elementum tristique. Duis cursus, mi quis viverra ornare, eros dolor interdum nulla, ut commodo diam libero vitae erat. Aenean faucibus nibh et justo cursus id rutrum lorem imperdiet. Nunc ut sem vitae risus tristique posuere.

Lorem ipsum
icon arrow right
icon close

Up next:

Close-up illustration of a handwritten signature, representing modern digital signing solutions.
Developers
15
minute read

Integrating Dropbox Sign with Ruby on Rails: A Step-by-Step Tutorial

Close-up illustration of a handwritten signature, representing modern digital signing solutions.
Developers
15
minute read

Dropbox Sign vs. SignNow for developers

Video

Digital collect Signed Waivers with Dropbox Sign

Products
Dropbox SignDropbox Sign APIDropbox FaxIntegrations
Why Dropbox Sign
Electronic signaturesSign documentsSign and Fill PDFsOnline contractsCreate electronic signaturesSignature editorSign word documents
Support
Help centerContact salesContact supportManage cookiesGetting started: Dropbox SignGetting started: Dropbox Sign API
Resources
BlogCustomer storiesResource centerLegality guideTrust center
Partners
Strategic PartnersPartners locator
Company
CareersTermsPrivacy
icon facebookicon youtube

Accepted payment methods

Mastercard logoVisa logoAmerican Express LogoDiscover logo
CPA Compliance BadgeHIPAA compliance badgeSky High Enterprise Ready badgeISO 9001 Certified badge

Dropbox Sign electronic signatures are legally binding in the United States, European Union, United Kingdom, and in many countries around the world.
For more information, please view our Terms and Conditions and Privacy Policy