There is no Android default
Apple ships one camera stack, so "iPhone 12 or newer records HDR" is a usable rule. Android has no equivalent. HDR recording depends on the manufacturer, the model tier, the camera app, and often a setting buried in that app rather than in system settings. Two phones released the same year from the same brand can differ.
That makes checking the file the only reliable step:
ffprobe -v error -select_streams v:0 \
-show_entries stream=color_transfer,color_primaries,pix_fmt \
-of default=nw=1 clip.mp4
arib-std-b67 or smpte2084 in the transfer field means the clip is already HDR. bt709 or an empty field means SDR.
Broad shape of the landscape
Recent Samsung flagships can record HDR10+, usually behind a toggle rather than on by default. Recent Pixel devices record HDR. Mid-range and budget devices across all manufacturers are overwhelmingly SDR, and many devices that can record HDR ship with it off.
Treat all of that as a prior, not an answer. The file settles it.
Third-party camera apps
A phone capable of HDR recording will often produce SDR through a third-party camera app, because HDR capture usually requires the manufacturer's own pipeline. If you shoot with anything other than the stock camera, assume SDR until the file says otherwise.
What you get
For genuinely SDR footage, conversion produces a 10-bit HDR10 file with BT.2020 primaries and the PQ curve, at the resolution and frame rate you uploaded. Highlights that were flattened against SDR's diffuse-white ceiling get headroom. Detail the sensor never captured does not come back.
Questions people ask
Which Android phones record HDR?
Recent Samsung flagships can record HDR10+ and recent Pixels record HDR, usually behind a toggle rather than on by default. Mid-range and budget devices are overwhelmingly SDR. Treat any list as a prior and check the file, because it varies by model and firmware.
Why does the same phone produce HDR in one app and not another?
HDR capture generally requires the manufacturer's own camera pipeline. A third-party camera app on an HDR-capable phone commonly records SDR, and some social apps re-encode on capture. If you did not shoot with the stock camera, assume SDR until the file says otherwise.