Migrating from v3

v3	v4
computeAmplitude(path, 100) returned an array synchronously	resample(await analyzeAudio(path), 100), or useWaveform. Values are RMS instead of the mean absolute level, which is very close visually.
Changing the sample count decoded the file again	resample the same Peaks
Returned [] for unreadable files	Rejects with a descriptive error
load(url) cached by file name and size	Caches by full URL; supports headers; rejects non-2xx responses. Files cached by v3 are never read again: clearCache() removes them, getCacheSize() counts them
react-native-nitro-modules ^0.27	^0.37.1

The helpers from the v3 example app map to:

v3 helper	v4
sample(values, n) (picked every n-th value, could skip peaks)	resample(peaks, n)
scale(values)	normalize(values) — keeps silence at 0
robustScale / trimmedScale	normalize(values, { reference: peaksLevel(peaks, { percentile: 0.99 }) })

The full list of changes is in the changelog.