Anybody who has tried to use a smartphone or tablet with long nails knows that there's a learning curve. Rather than effortlessly tapping with a fingertip, you must awkwardly lay the pads of your fingers onto the screen. Wouldn't it be easier if you could just type with your fingernails instead? To try and make this idea a reality, a group of researchers is formulating a clear nail polish that could turn long fingernails into touchscreen-compatible styluses.

To find the perfect combination of clarity and conductivity, Desai turned to good, old-fashioned trial and error. Using 13 commercially available clear-coat polishes and more than 50 different additives, she slowly worked her way through the combinations to find which ones resulted in a conductive topcoat for nails. The molecules that performed the best were forms of taurine, an organic compound commonly sold as a dietary supplement, and ethanolamine, another simple, organic molecule.

These initial results are promising, but the team still has a long way to go before the polish will be available on store shelves. Even the best-performing ethanolamine-taurine formula is finicky and doesn't yet work consistently when painted on a nail. Plus, ethanolamine evaporates quickly, so the polish only works on a touchscreen for a few hours once outside the bottle, and researchers would prefer a truly nontoxic compound.

Despite these setbacks, the researchers now have an idea of how the successful formula works, and they are continuing to screen compounds and test new formulas to find the best-performing combination.