You can do a lot on a smartphone, from depositing a check to ordering groceries.
But here's one thing you can't do: vote for elected officials.
Some advocates see the potential of a more modernized system amid concerns about US election security and aging voting machines.
A major reason people don't vote is because they can't get to the polls, according to John Patrick, author of "Election Attitude: How Internet Voting Leads to a Stronger Democracy."
"This old system does not accommodate the busy people we are today and the people who are sick, in nursing homes, [or] in the military," he said. "There are a hundred reasons why people can't vote."
But to keep smartphone voting safe, experts are looking toward blockchain technology, a super secure and transparent public ledger with the history of transaction data from anyone who uses a certain service. Although blockchain is most associated with powering cryptocurrencies like bitcoin, it can be applied to other areas, such as health care or voting.
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Blockchain uses a decentralized network of computers that all work on the same task -- and no one entity owns the system.
This means when a transaction is initiated between two computers, such as casting a vote, it has to be certified by another. That makes it difficult to manipulate or change the data. For the transaction to go through, a bunch of computers have to solve a complicated math problem.
But that doesn't mean Americans will be tapping smartphones to elect officials anytime soon. Some voting security experts are wary of applying the technology to major elections.
Voters could fall prey to phishing scams, viruses and malware on their smartphones or laptops, even if a blockchain-based voting system is secure, according to David Dill, a professor emeritus of computer science at Stanford University who studies electronic voting.
"Smartphones and laptops aren't secure, and at this point, they can't be made secure," he said. "People could be tricked into something that's malicious."
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However, a startup called Votem argues mobile voting has the potential to boost voter turnout, increase accuracy and reignite trust in election results. The company says it can verify and count votes in real time on its blockchain-based voting platform.
The company, which began operating in early 2016, has tested its system with several private elections, including for the Rock & Roll Hall of Fame and the Ohio State Bar Association. Meanwhile, Votem tested a non-blockchain version of its platform during the 2016 general election, such as running online voting and registration for people serving in the military and US citizens living overseas for Washington, DC.
Votem allows users to register and vote via its mobile app or a desktop computer, and then serves up a ballot. The system creates "nodes" from mathematical algorithms to determine the ballot's legitimacy. For example, the nodes examined if the vote came from a bad IP address or if it's a real voter.
To date, more than 8 million votes have been cast using Votem across private elections. The company hopes to offer this method to several jurisdictions for the 2018 midterm elections.
US elections still largely rely on paper ballots. Most voting machines used to cast and count votes were bought between 2002 and 2008, according to the National Conference of State Legislatures, a bipartisan and non-governmental organization. Some small municipalities in states such as New Hampshire even count votes by hand.
"[As of today], you still have to physically go to the polling place and fill out a paper ballot" Pete Martin, Votem's CEO and founder, told CNN.
He said replacing the current process with newer technology will only make a "bad process faster."
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Other startups, such as Voatz in Boston and Smartmatic in London, are also testing blockchain-based voting systems. But these companies face many challenges.
"This industry is very resistant to change," Votem's Martin said. "The risks are incredibly high for getting this right. There is nothing more fundamental than a fair voting system."
In addition, certifying new voting systems in the US is a complicated process, and the requirements vary by state.
For now, security experts remain skeptical.
"Online voting for government elections is a horrifically bad idea," said Joseph Lorenzo Hall, chief technologist at the Center for Democracy & Technology, a nonprofit that promotes an open and free internet. "The internet, and more importantly the devices we use, are completely insecure."
Although Joe Kiniry -- CEO and chief scientist of Free & Fair, a company focused on election technologies and services -- says blockchain voting could potentially be a useful solution for private elections, it's a risky method for government elections with a lot at stake.
"Internet voting and blockchain are all about putting voters and computers directly on the internet to run an election. It's putting the tastiest target in the world politically directly on the threat vector [of] all these bad actors out there," Kiniry said. "We have to assume they will use their most advanced technology and capabilities to threaten that election."
Some experts like Stanford's Dill believe paper ballots are the best voting method for now. He also advocates for auditing the results by taking a random sample and counting those votes by hand to double check the results.
"Maybe internet or blockchain voting could be the thing at some future point, but it's not ready for prime time yet," Dill said.
