How to Charge a Phone With Another Phone
Running out of battery with no outlet in sight is one of those genuinely frustrating modern problems. The good news: depending on what phones are involved, you may be able to use one device to charge another. Here's how it actually works — and what determines whether it'll work for you.
The Technology Behind Phone-to-Phone Charging
The feature that makes this possible is called Wireless Power Share, Reverse Wireless Charging, or simply reverse charging — the name varies by manufacturer. The concept is the same across all of them: a phone that normally receives wireless charge can, in certain configurations, transmit that charge to another device.
This works through the same Qi wireless charging standard used by charging pads. A Qi-compatible phone can act as a transmitter, turning its own battery into a power source for any Qi-compatible receiver placed on its back.
There's also a wired version. Using an OTG (On-The-Go) cable, some Android phones can push power through their USB port to another device. This is a different mechanism — it uses a physical cable rather than induction coils — but achieves a similar result.
Which Phones Actually Support This 📱
Not every phone can do this. Reverse wireless charging is a hardware feature — the device needs induction coils capable of both receiving and transmitting power. It's typically found on mid-to-high-end Android phones, and availability varies significantly by brand and model generation.
Many flagship-tier Samsung Galaxy, Huawei, Xiaomi, OPPO, and Google Pixel devices have included this feature. Some phones that support receiving wireless charge do not support transmitting it — the coils are one-directional in those cases.
iPhone is a notable example of a gap here. iPhones support receiving wireless charge (MagSafe and Qi), but Apple has not enabled reverse wireless charging on consumer iPhones as of recent generations. An iPhone cannot wirelessly charge another phone.
For OTG wired charging, support depends on the USB controller in the phone. Many Android devices support USB OTG, but not all — and even among those that do, the power output varies.
How to Enable Reverse Wireless Charging
On supported Android devices, the process is generally straightforward:
- Open Settings
- Search for "wireless power share," "reverse charging," or "battery share" — the label varies by brand
- Toggle the feature on
- Place the device to be charged back-to-back with the transmitting phone, aligning the charging coils (usually centered on the rear panel)
The receiving device needs to be Qi-compatible — that could be another phone, wireless earbuds, or a smartwatch.
For OTG wired charging, you need an OTG-compatible cable or adapter. Connect the source phone (the one with battery) to the device being charged. Some phones prompt you to confirm the power direction; others handle it automatically based on which device has more charge.
What Affects How Well It Works
Phone-to-phone charging works — but its usefulness depends on several variables:
| Factor | What It Affects |
|---|---|
| Transmitting phone's battery level | Most devices won't reverse charge below 20–30% to protect their own battery |
| Wireless charging wattage | Reverse wireless is typically slow — often 3W to 5W, much less than a wall charger |
| Coil alignment | Poor alignment drops efficiency; precise placement matters |
| Phone cases | Thick or metal cases can block or degrade the wireless signal |
| OTG cable quality | Cheap cables can limit current flow and slow charging |
| Receiving device compatibility | The device being charged must support Qi or USB charging as applicable |
The wattage point is worth emphasizing. Even phones that support fast wireless charging when receiving power typically transmit at much lower rates when acting as a charger. You're likely looking at a slow trickle of charge — useful in an emergency, not a replacement for a wall charger or power bank.
Wired vs. Wireless Phone-to-Phone Charging ⚡
These two methods serve slightly different scenarios:
Reverse wireless charging is convenient but slow. It's best for topping up a device just enough to make a call or send a message — not for meaningful battery recovery. Both phones need to stay stationary and in contact during the process, which limits how usable either device is in the meantime.
OTG wired charging is generally faster and more efficient than the wireless version because less energy is lost in the transfer. It also doesn't require both devices to support wireless standards. However, it requires the right cable, and not all phones support OTG output.
The Practical Limits to Understand
A few things are worth being clear about before relying on this feature:
- You're draining one phone to charge another. If both devices need to last the day, transferring charge may leave you with two half-empty phones instead of one full one.
- Heat is a factor. Both phones generate heat during the transfer, and sustained use can cause the transmitting phone to throttle or pause the session.
- This is an emergency feature, not a daily solution. For regular top-ups away from outlets, a compact power bank transfers energy far more efficiently than phone-to-phone methods.
The Variables That Define Your Situation
Whether phone-to-phone charging is genuinely useful comes down to a specific combination: which phones are involved, whether the hardware supports the method you're trying, how much battery each device has, and what you actually need the charge for.
Someone with two compatible flagship Androids and a quality OTG cable is in a meaningfully different position than someone with an iPhone and a Qi-only Android device — or two phones where only one supports reverse wireless. The feature exists across a wide range of devices, but the experience isn't uniform, and the gap between "technically supported" and "actually useful in your situation" can be significant depending on your specific hardware and how you need to use it.