For years the standard recipe for a cheap home camera was a Raspberry Pi, a Camera Module and a motionEye install. That recipe still works, but it is no longer the cheap one. If a spare Android phone is already in a drawer, it already contains the sensor, lens, processor, Wi-Fi radio, speaker, microphone, screen and a battery backup, and AndrIoT turns it into a camera you watch from a browser in about ten minutes.
This is not an argument that the Pi is pointless. It compares what each really costs, how long the build takes, what it draws from the wall, what fails in year two, and the jobs where a Pi is still the right tool.
Key takeaways
- A Pi camera build is mostly not the board: board, power supply, card, camera and case add up to roughly $99 to $134 at typical prices.
- A phone you own needs a stand and a charger; the running cost is an AndrIoT plan, $49.90 a year on Standard for up to 5 phones.
- Power draw is closer than people expect. Both sit in the low single-digit watts, so electricity is a few dollars a year either way.
- The Pi still wins on wired Ethernet and PoE, GPIO sensors, having no battery, and software you control end to end.
- The phone wins on time, cost and built-in features, but it has no infrared camera, no weatherproofing and a battery that ages.
What a Pi camera build really costs
Prices below are rough street prices in US dollars at the time of writing, before shipping and taxes. They move, so treat them as a shape rather than a quote. The point is which lines exist at all.
| Part | Typical price | Note |
|---|---|---|
| Raspberry Pi 5 (2 GB) or Pi 4 (2 GB) | $50 to $60 | The board alone does nothing without the rest |
| microSD card, 32 GB | $8 to $12 | Use a high-endurance card, because this part wears out |
| USB-C power supply | $8 to $12 | Underpowered supplies cause random reboots |
| Camera Module 3 | $25 to $35 | The wide version costs more |
| Case | $8 to $15 | Needs airflow |
| Total | $99 to $134 | Before any outdoor enclosure |
Now the phone path, assuming the phone is already yours.
| Item | Cost | Note |
|---|---|---|
| Old Android phone | $0 | Already in a drawer |
| Stand or clamp | $5 to $15 | A shelf with a lip also works |
| Charger and cable | $0 to $10 | Use the original if you still have it |
| AndrIoT Standard, one year | $49.90 | Up to 5 phones, 7 days of history, 1080p |
| Year one total | $55 to $75 | Nothing else is required |
That asymmetry is the whole argument. The board is the cheapest line on its own list because everything a camera needs sits around it: power, storage, a case, a lens and a network connection to configure. The phone arrives with all of it, plus a screen and speaker for two-way audio.
Time to set up
A first Pi camera is an evening, not ten minutes. The steps are documented and none of them is hard, but there are six of them and each has its own failure mode.
- Flash the operating system to a card and boot it without a monitor.
- Update the system and enable the camera interface.
- Install a streaming server or a motion daemon and write its configuration.
- Point recordings at storage and arrange remote access through a VPN or reverse proxy.
- Tune motion thresholds, which is where most of the time actually goes.
Plan on one to three hours for a first build, more if a ribbon cable or a driver update fights you. The phone side is a download, a six-step wizard and a pairing code: about two minutes to pair, and the evening goes on placement and tuning. The setup guide walks through it step by step.
Power, heat and the battery question
Both are low-power devices, and the difference is smaller than the argument suggests. To turn watts into kilowatt-hours, multiply by 8760 hours and divide by 1000.
| Setup | Typical draw | Per year, running constantly |
|---|---|---|
| Pi 5 with Camera Module | about 3 to 6 W | about 26 to 53 kWh |
| Pi Zero 2 W with camera | about 1 to 2 W | about 9 to 18 kWh |
| Old phone streaming on a charger | about 2 to 4 W | about 18 to 35 kWh |
Those are estimates from typical draw, not measurements, and they all land in the same few-dollars-a-year band. The real difference is what is inside the box. A Pi has no battery, so nothing swells after two years on a charger. A phone does, which is why the 24/7 power guide exists and why a monthly look at the back cover is part of the routine. Both need airflow: a Pi in a sealed case throttles, and a phone under a cushion gets hot.
Maintenance over a year
This is where the two builds diverge most, and it rarely appears in a shopping list.
- The Pi's weak point is the card, and updates. A constantly written microSD card fails eventually, so use an endurance card and keep a copy of the image; pinned versions avoid an upgrade that breaks the camera stack.
- The phone's weak point is the battery. Check for swelling monthly, keep the app exempt from battery saver, and retire a phone whose battery is finished instead of leaving it on a charger.
- Both need physical checks. Dust on the lens, a sagging mount and a pulled cable miss more events than software does.
Where a Raspberry Pi is still the better tool
There are jobs a phone genuinely cannot do, and pretending otherwise would be dishonest.
- Wired Ethernet and PoE. One cable for power and data, no Wi-Fi dropouts, no reconnects. Phones are Wi-Fi devices.
- GPIO sensors. A reed switch on a gate, a PIR, a relay, a temperature probe: real inputs and outputs on real pins. A phone has its own sensors, but you cannot wire a door contact into it.
- No battery. Nothing to swell, nothing to cycle, nothing to replace. A headless Pi with an SSD can run for years.
- Your own software. RTSP, ONVIF, local-only storage, a home-automation integration, no account anywhere.
- Infrared, done properly. A NoIR camera module with a separate IR illuminator gives real night vision. A phone has no IR emitter at all.
- Outdoors. In a proper enclosure with PoE, a Pi is a fixed installation. A phone is not weatherproof.
Where the phone wins
- Cost and time. $55 to $75 for the first year against $99 to $134 unconfigured, and minutes rather than an evening.
- Features you would otherwise build. Battery backup, two-way audio, a screen, text-to-speech, light and temperature readings, and an IR blaster on phones that have one.
- Alerts that already work. Push notifications, Telegram on Standard and Pro, webhooks and MQTT on Pro.
Decision table
| If this is your situation | Reach for | Why |
|---|---|---|
| One indoor camera, this weekend, lowest cost | Old phone | No hardware, minutes to pair, plan covers up to 5 phones |
| Outdoor camera, rain and dust, all year | Pi in an enclosure, or a weatherproof IP camera | A phone is not weatherproof |
| Door contact, PIR or relay automation | Raspberry Pi | GPIO is the feature a phone cannot offer |
| Real night vision | Pi with a NoIR camera and illuminator | No phone has an IR emitter |
| Talk to a visitor or a pet | Old phone | Speaker, microphone and two-way audio in the box |
| No account, no cloud, no subscription | Raspberry Pi | Self-hosted and free after the hardware |
Pros and limits
Pros of the phone route
- No hardware to buy if the phone already exists.
- Setup measured in minutes.
- Battery backup, speaker, screen and sensors included.
- Alerts and remote viewing without port forwarding.
Limits
- No infrared, so no night vision.
- Not weatherproof: indoors or behind glass only.
- Must stay powered and on Wi-Fi.
- Object detection recognises broad classes (person, pet, vehicle), not faces.
- The battery ages and needs checking.
Sources of truth and honest limits
The prices and power figures above are assumptions, not measurements: prices are typical street prices in USD, and the kilowatt-hours come from the stated wattages over 8760 hours. AndrIoT's numbers come from the published plans: Standard is $4.99 a month or $49.90 a year for up to 5 phones, 7 days of history and 1080p; Pro is $9.99 a month or $99.90 a year for 10 phones, 30 days, and webhooks plus MQTT. Live video is peer-to-peer and encrypted, with an encrypted relay when a direct path is blocked, and nothing is recorded unless you enable it. The Privacy Policy and Terms describe the rest, and the home page lists every feature. Where the phone falls short we say so: no IR emitter, no weatherproofing, a battery that ages, and on-device detection limited to COCO classes with no face recognition. If you want a wired, headless, GPIO-driven camera, the Pi is the better tool. For the broader comparison, see what a phone camera really costs and who can see your video.
FAQ
Can an old phone really replace a Raspberry Pi camera?
For one indoor camera you watch in a browser, yes, and it runs in minutes. It cannot replace GPIO pins, wired Ethernet, weatherproofing or real infrared night vision.
Which is cheaper in the first year?
The phone, if you own it: about $55 to $75 with a stand and a Standard plan, against roughly $99 to $134 for a Pi build. From year two the Pi has no subscription, so the totals converge.
Does a phone use more electricity than a Pi?
About the same. A phone draws roughly 2 to 4 W while streaming, a Pi 5 with a camera about 3 to 6 W, and a Pi Zero 2 W less than either.
Can I run a phone camera without a subscription?
Only the demo is free; a real phone needs Standard or Pro. A self-hosted Pi camera has no monthly fee, which is its main long-term advantage.
What about night vision?
Neither a phone nor a plain Pi camera module sees in the dark. A Pi can take a NoIR camera and an IR illuminator; a phone has no IR emitter, so add a night light.