Fact · Dictation on phones and tablets
Apple says that setting requiresOnDeviceRecognition stops the request sending audio over the network, and that on-device requests are less accurate.
Checked against its source on October 17, 2026
In the source's own words
“from sending audio over the network. ... However, on-device requests won’t be as accurate.”
requiresOnDeviceRecognition (Speech framework documentation), Apple Inc., n.d., Discussion.
Open the original- What it measures
- Apple's reference for the requiresOnDeviceRecognition property of SFSpeechRecognitionRequest, read on 2026-10-17. The property is honored only when the recognizer also supports on-device recognition.
- What it does not show
- Apple does not measure the accuracy gap, so this is a direction, not a size. Test your own sentences in each language before you rely on on-device results.