Both the PCR and Cue Health test are Nucleic Acid Amplification Tests (NAATs). As per the CDC classification, there are 2 main types of NAATs, RT-PCR and Isothermal Amplification.
Cue Health test is an Isothermal Amplification test. The Cue Health test has the highest correlation with PCR as seen in a recent Mayo clinic study where it  correlated 98% of the time with PCR testing.