 Penny stocks are notoriously risky investments because theyre often speculative in nature. With that said, investors who are willing to take on a relatively high level of risk could find them to be a good way to play the current market uncertainty. With the novel coronavirus still looming and equity prices climbing ever higher, looking for penny stocks to buy could be a good way to find value.Laura Gonzalez, Ph.D, an Associate Professor of Finance at California State University, Long Beach, said penny stocks deliver the most value when theyre more-or-less undiscovered. As trading volume increases, the wider market starts to pay attention. Historical data shows that penny stocks receive less attention from investors, are oftentimes undervalued and underpriced, and therefore poised to deliver superior returns. When superior returns materialize, analysts and other investors notice them, but the attention is not sustained for a long time.InvestorPlace - Stock Market News, Stock Advice Trading TipsThat phenomenon has become apparent in the current climate as investors using no-fee platforms take a notable interest in penny stocks. Gonzalez warns that come autumn, investors may start to favor other types of investments to combat a market downturn.Especially in crisis times, it is likely that investors will try to offset potential market downturns in Fall with alternatives other than penny stocks, such as cryptocurrencies this year. This sector experienced a run-up from February to April, in part because of cryptocurrencies being considered digital gold and the conversations in DC about a future Fedcoin.Penny stocks arent for everyone -- especially not those who want to buy stocks and hold on to them forever. Instead, penny stocks are best bought by those who can take on a relatively large degree of risk and are willing to keep a close eye on market developments. 7 Dividend Stocks to Buy for Beginners to Income Investing With that in mind, heres a look at a handful of penny stocks that are worth considering. XpresSpa Group NASDAQ:XSPA Foresight Autonomous Holdings NASDAQ:FRSX NovaBay Pharmaceuticals NYSE:NBY Color Star Technology NASDAQ:HHT Exela Technologies NASDAQ:XELA Digital Ally NASDAQ:DGLY iBio Inc NASDAQ:IBIO ExpresSpaSource: UfaBizPhotoShutterStock.com ExpresSpa gained a ton of attention in June when the firm announced plans to pivot its in-airport spa business into coronavirus testing sites. While the decision to shift focus toward the pandemic sounds like a good plan, its worth noting that in the longer term, its a terrible business plan.Not only will the firm struggle because of its lack of experience in the medical space, but the company is also pushing a paid service that others, like CVS Health NYSE:CVS and government agencies, are offering for free.Still, XSPA stock has been a penny stock to watch because if the company is able to pull off the transition, its genius. So, while I wouldnt buy XSPA as a long-term investor, it makes sense as a speculative play.Recent XpresSpa job postings suggest the firm may be about to announce a new testing location in Newark, representing a major win for its expansion plans. With investors already keeping a close eye on XSPA, that kind of news could cause another jump upward. Foresight Autonomous HoldingsSource: Shutterstock FRSX stock is another pandemic play, but unlike XSPA, this firm does have a great deal of long-term potential. Foresight has been on a tear since June after it announced that it was creating a way to screen for coronavirus symptoms in large groups. It recently began a pilot program for its mass screening technology, which uses thermal camera technology to search for potentially infected individuals. 10 Gaming Stocks That Will Power Through the New Normal It goes without saying that if FRSX is able to obtain a patent for its screening technology, it could be a huge leap forward. Plus, if its pilot program is deemed successful, the news could push the stock higher, especially as new coronavirus cases are expected to surge in the fall. NovaBay PharmaceuticalsSource: Iryna Imago Shutterstock.com There are a lot of drugmakers working on treatments and vaccines that have become enticing bets for speculative investors. But theres one penny stock worth considering because of its unique product that could soon be in everyones Amazon shopping cart.NovaBay recently revealed that its disinfectant, Avenova, was shown to be effective in killing the strain of coronavirus that caused the global pandemic. The test results have been sent to the EPA in hopes that Avenova will eventually make its way onto the organizations list of disinfectants approved to kill SARS-CoV-2. What makes NBY stock a compelling buy is the uniqueness of Avenova, which has been on the market for some time as an eye treatment. The product is gentle enough to be used on the skin, including the area around your eyes and nose.Not only will that make the use case for Avenova much stronger, but it will also make it a good option as a disinfectant for vulnerable groups like young children. Harsh chemicals being used to clean toys and other surfaces can be dangerous for babies, but a more gentle solution could prove popular in the fight against the pandemic. Color Star TechnologySource: Shutterstock With school reopenings postponed in some states and many medical experts warning of a dangerous second-wave of coronavirus cases, educational technology is a field that cant be overlooked.HHT stock is a unique play in that space for a few reasons. First, theres the fact that the firm is headquartered in China, where the government imposed some of the strictest lockdown rules when the virus broke out. For that reason, its safe to assume that if a second wave happens, Chinese children will be out of school immediately.The second reason is that the firm appears to be finding a way to create some sort of an Amazon of Ed-tech. It recently partnered with Morremoon in an effort to improve the digital animation aspect of its services. The partnership, HHT says, is the start of a new kind of digital education platform that will offer online classes as well as supplementary products. It aims to merge online education with online shopping. 7 Cybersecurity Stocks Hard At Work While We Work From Home This could become an effective way of creating a quality homeschool environment in which parents have access to a greater variety of resources to supplement the online classrooms. Now imagine the ad revenue and sponsorship deals Color Star could capitalize on if online learning sticks around. Exela TechnologiesSource: Shutterstock Traditional Edtech isnt the only place to go looking for value in a world plagued with coronavirus. XELA stock is another one to keep on your radar as its technology will eliminate the need for person-to-person contact within brick-and-mortar schools. The firm says its Intelligent Lockers will make it safer for both students and faculty returning to school. XELA tweeted that the lockers could be used on college campuses in order to provide a contact-less mailroom experience.Excela is more than just a locker-maker though. The firm also offers document scanning technology as well as a confirmation of Payee Platform through a partnership with Co-operative Bank. Digital AllySource: Digital AllyIf there were one stock that capitalizes on every bit of market uncertainty, it would be DGLY stock. The firm is best known for its body cameras, but it also offers non-contact temperature scanning technology.When protests calling for police reform spread across the country, Digital Allys body cams were in focus as more counties made wearing the devices mandatory. Concerns about accountability for the police arent going anywhere, and for now, body cams are the fast solution.But DGLYs temperature scanners are the reason the stock is seeing investor attention right now. TrustThink Products just ordered 500 of its temperature screening devices as many U.S. states try to keep their economies open despite surging coronavirus cases. In the absence of a vaccine, temperature checks are one of the few ways businesses can try to make their locations safe for customers. 10 Cybersecurity Stocks We Need Now More Than Ever DGLYs temperature scanner is more than just a thermometer, though. It can be used to control access into a facility based on whether or not a persons temperature is elevated. It also has facial recognition technology making it useful for security as well. iBioSource: Shutterstock Its impossible to talk about penny stocks without including at least one potential vaccine maker. Choosing the winning biotech stock in the race to develop a Covid-19 vaccine is inherently risky because not only are there a lot of potential contenders, but theres also a chance that an effective vaccine isnt possible.However, if you do pick the right stock, it could be a huge money-maker. IBIO stock looks like it could be a potential winner in the vaccine race. Not only is iBio trialing two vaccine candidates, but theyre two of only a handful that require only one dose.iBio was chosen by IBM NYSE:IBM to use the Watson supercomputer free of charge to develop its coronavirus vaccine, marking a huge leap forward for IBIO stock. Thats because not only does that add a layer of confidence, but it also means the firm will have added resources to push a successful vaccine out faster than competitors without access to Watsons technology. In the near-term, IBIO stock looks overdue for a boost as the firm hasnt said much regarding progress on its vaccines. When the company does come out with hopefully positive data, it will send iBio stock higher. 