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LFAs are currently rare, but due to their advantages of being quick and useable at the point of care, some healthcare professionals have suggested that as a format for antigen and antibody (serology) testing, they could positively change the testing landscape. As of September 2021, 25 of 88 serology tests that have received EUAs by the FDA are explicitly labeled as being LFAs, with 12 of those 25 being approved for POC/CLIA-waived use. An article by Sheridan in Nature Biotechnology highlights a handful of others developed around the world (see their Table 1). FIND shows more than 400 commercialized rapid diagnostic immunoassay tests around the world, though it's not clear how many of them actually LFAs (from their list, only 14 are explicitly stated as being LFA). While LFAs have increasingly been approved around the world in 2021, it remains a question whether or not we continue to see more of them, at least in the United States.

Also of note are isothermal amplification methods. Abbott's ID NOW and Cue Health's Cue COVID-19 and Cue COVID-19 Test for Home and OTC tests (the latter being the first isothermal amplification test approved for home use) are described by the FDA as using "isothermal nucleic acid amplification technology for the qualitative detection of SARS-CoV-2 viral nucleic acids." Isothermal amplification tends to be an easier process to manage due to being able to keep amplification at a constant temperature. In fact, Abbott has stated its EUAed ID NOW COVID-19 test can be completed within five minutes. However, May 2020 findings by New York University put the test's accuracy into question. On July 1, 2020, an FDA spokesperson allegedly indicated receipt of 126 reports of "adverse events" concerning the test. In 2020, some 393 complaints were reported to the FDA, with 1,492 complains being reported in 2021 (through July 31) according to an FDA MAUDE (Manufacturer and User Facility Device Experience) search. The FDA was reportedly investigating the data and working with Abbott to have additional studies performed on the test's accuracy in 2020. In October 2020, Abbott released additional study data showing overall sensitivity of 93.3% and specificity of 98.4%, emphasizing the ID NOW's best use with samples taken within seven days of symptom onset. On August 27, 2021, the FDA re-issued its EUA for the ID NOW with updated in silico inclusivity analysis results (among other things), but it's not clear if the FDA is continuing to work with Abbott on the test's accuracy claims.

Specific isothermal amplification techniques called loop-mediated isothermal amplification (LAMP) and reverse transcription LAMP (RT-LAMP) are beginning to emerge as options for COVID-19 testing. For example, Talis Biomedical is developing the Talis One COVID-19 system for point-of-care testing. It has received National Institutes of Health's Rapid Acceleration of Diagnostics (RADx) funding and, should it receive its EUA (as of August 2021, it was still awaiting FDA authorization), is expected to be among the first U.S.-approved RT-LAMP tests for COVID-19. In November 2020, the first LAMP-based, prescription "collect and test" at-home kit—the Lucira COVID-19 All-In-One Test Kit—was approved by the FDA for emergency use. Globally, examining FIND's list of nearly 280 commercialized manual NAAT tests around the world, five of them are explicitly shown to be some form of LAMP test. Multiple preprints on medRxiv and bioRxiv, as well as published papers, suggest that RT-LAMP could provide rapid results for SARS-CoV-2 testing. However, it's apparent that adoption of LAMP as a COVID-19 test technique has been slow at best overall.