just had the chance to participate in what officials say

is the country's most extensive use of mobile voting yet.

Over 95% of the election's ballots

were submitted electronically, via app or website.

- Supporters of mobile voting say,

"If you let people cast their ballots on their phones,

"they're a lot more likely to do it

"because it'll be easier and take less time."

- [Narrator] But some experts warn

that voting on our phones creates new privacy

and security problems that we don't have solutions for.

Will it always be too risky for a presidential election

or is nationwide mobile voting only a matter of time?

- At the end of the day, voting software is still software.

And all software is buggy.

And there will always be errors and security holes.

It's impossible to build perfect software.

- [Narrator] A tech company called Democracy Live

built the system that Washington voters used

during the recent pilot.

And while Democracy Live agrees that both software

and humans can be fallible, they're confident

their system is still safer

than some methods currently in use.

- King County, which is Washington's state

most populous county recently allowed mobile voting

for over one million voters in a small, local election.

Voters could use their phones or their laptops

to log onto a portal, open up a ballot and then

they could choose to submit that ballot electronically,

which is what we would think of as mobile voting.

- [Narrator] Supporters of mobile voting

say that it will make the process more convenient

and boost voter turnout.

In King County, election officials say

that turnout this year was double what it was

for this election last year.

Most of the roughly 6,500 ballots

were submitted electronically.

Only 209 were submitted by mail or drop box.

- If I had to choose between submitting a paper ballot

or using the app on my phone,

I actually would do the paper ballot.

We have a lot of experience with paper ballots over time.

And so there's kind of a big field test out there

that's been going on for decades.

And we know that it's not easy to change

a large number of paper ballots.

My concern about the digital environment

is that once those votes are collected

in a single database, the possibility

that someone could manipulate a large number of votes

at once is much higher.

Even more importantly is the fact that other people

would potentially fear that that would happen.

- [Narrator] Even under the best circumstances,

introducing new election technology

can add a new layer of doubt to results.

- In Iowa's caucus', the state Democratic Party

wanted to use an app to collect and report results

because they thought it would make it faster and easier.

Unfortunately, based on our reporting,

the app wasn't put through enough testing

and there wasn't enough planning.

So it ended up having glitches

that have really caused problems

for figuring out what the results were in Iowa.

- There was a sense that maybe it just didn't work

the way it was supposed to work.

And just introducing that amount of doubt

into the system delegitimatizes

people's confidence in the vote.

And it doesn't, I think, give people a high level

of confidence that we can manage

this sort of digital layer on top of what is already

a pretty emotionally-fraught voting system.

- Advocates are worried after what happened in Iowa

that people will start to be scared

of using new technology for voting.

Supporters of mobile voting say,

"They focus on security.

"They plan in advance and that they don't think

"what happened with Iowa's app should have

"a negative impact on their separate efforts."

- [Narrator] Running an end-to-end test

is crucial in most software development.

Creating software for smart phones

presents a unique challenge when it comes to testing,

which is especially important

when creating voting technology.

- We're building it so that it can run on

all the thousands of possible combinations

of Android phones, and IOS phones

and even Microsoft phones and phones

who's operating system haven't been updated

in three or four years or even more.

And so there's almost a limitless number

of environments in which you have to prove

that software can work.

And it's almost impossible to test it

in all of those environments except,

in an actual election.

- [Narrator] Still, mobile voting supporters say

it's important to find ways

to improve access and engage voters.

- Some experts and some people who advocate

for mobile voting say it's inevitable.

They say that younger generations

are used to doing everything on their phones

and they want to meet voters where they are.

- Maybe when every single car on the road

is driven by a robot and a generation of people

can't even imagine that a human being

would have ever driven a car, we'll also be saying,

"God, can you imagine that people used to vote

"on pieces of paper?"

I can see that coming and I think we'll be there,

but I think it's 20 years, not 10.

(upbeat cheerful music)