At-home tests have become an easy way to self-diagnose Covid-19, but tests such as the commonly used lateral flow have drawbacks, such as the length of time it takes to get an answer, or how accurately the test can identify a positive case.

Most of them also require the uncomfortable procedure of sticking a swab up one’s nose.

Though PCR tests are known as the “gold-standard” because of their high sensitivity and specificity for Covid-19, it requires the sample to be sent away to a lab and be analysed by specialised personnel.

The analysis itself can take up to an hour, but the total time from swab to answer can take days.

The prototype device combines speed with PCR levels of sensitivity while only requiring a saliva sample, a palm-sized, portable device and a smartphone...