Most people who want to record a lecture reach for video. Most of the time, audio would do — and it is far easier. Here is how to decide, and how to set up either one so the recording is worth having afterwards.
Ask first
Many universities and lecturers have a policy on recording, and lecture material can be covered by copyright. Check the course rules, and ask the lecturer when in doubt. For personal study, the answer is often yes.
If you need recordings because of a disability or a learning difference, your institution’s accessibility or disability services office can usually arrange permission for you.
Video or audio: a quick decision
| Your lecture | Record |
|---|---|
| Mostly talking, slides shared afterwards | Audio |
| Whiteboard work, derivations, diagrams drawn live | Video |
| Demonstrations, labs, studio or practical classes | Video |
| Slides not shared, or changed during the lecture | Video |
| You mainly replay it on walks or commutes | Audio |
Recording audio well
- Use Voice Memos. It keeps recording with the phone locked and in the background, so you can use the phone normally, and an hour of audio takes a small fraction of the space of an hour of video.
- Distance matters more than anything else. A seat near the front, or the phone on the desk closest to the lecturer, beats any setting.
- Keep the phone still. Handling noise is louder in a recording than it feels in your hand.
- Tidy it up afterwards. Voice Memos can enhance a recording to reduce background noise, and during playback it can skip silences and change the speed.
- Name it straight away — the course and the date — so a term of recordings stays findable.
Recording video well
- 1080p is enough to read slides and a whiteboard from a sensible seat. 4K rarely earns its storage in a lecture.
- Use a stand. Nobody holds a phone steady for ninety minutes. Put it low, at the end of a row, where it blocks nobody’s view.
- Frame the board, not the room. Use the 1× lens and sit as close as you can; digital zoom softens text.
- Lock the focus. In the Camera app, touch and hold on the board until focus and exposure lock, so the picture does not hunt every time the lecturer walks past.
- Turn on airplane mode, so a call does not end the recording.
- Charge first and check free storage. How much storage does an hour of iPhone video take? has the numbers.
Video also means the recording app has to stay on screen the whole time — switch apps and it stops. How to keep using your iPhone while it records video covers the workarounds.
Keep the screen from distracting the room
A lit screen in a dim lecture hall distracts the people behind you, and the lecturer. Dim it, or use an app that records with the screen dark so it won’t light up the room. In NoLight, the screen goes dark with a REC mark left on it. The free version includes 10 minutes of dark screen in total, and NoLight Pro removes that limit — and lets you take notes in Workspace while the lecture records.
Making recordings useful afterwards
- Note the time of key moments while the lecture runs — “14:05 exam topics” — so you can jump straight there later.
- Review soon. A recording watched the same week is revision; one watched before the exam is a second lecture you do not have time for.
- Keep it to yourself. Recording for your own study is one thing; sharing it usually needs the lecturer’s permission.
- Delete what you no longer need. Lecture video fills a phone quickly.
Short answers
Should I record lectures as video or audio? Audio, unless the board or demonstrations matter.
Can I record a lecture with the iPhone locked? Audio, yes — Voice Memos keeps recording. Video needs the recording app open; a dark screen is as close as it gets.
Is 1080p enough to read slides? From a reasonable seat, yes.
Is it allowed to record a lecture? It depends on the institution’s rules and on where you are. Ask.