Explainer
How Does Auto Backup While Charging Work?
⚡ Key takeaways
- Auto backup while charging uses a small adapter that sits between your phone and its charger; when the phone charges, a companion app copies new photos and videos to a memory card inside the adapter.
- The backup is incremental — the first run copies the whole camera roll, and every later session copies only the files added since the last one.
- It works entirely offline over the physical connection, so there is no cloud account, no subscription, and no internet required.
- On a backup cube the storage is a user-supplied microSD card, which keeps the device cheap and lets you choose your own capacity.
- For iPhone the adapter must be Apple MFi-certified so it keeps working through iOS updates.
The clever idea behind auto backup while charging is that it attaches a chore you forget — backing up — to a habit you never forget: plugging your phone in at night. You do nothing different, and your photos get copied automatically while you sleep.
But how does it actually work under the hood? This explainer walks through the hardware, the software, and the "incremental" backup logic, so you understand exactly what is happening each time you charge — and where this approach fits versus the cloud.
The basic idea: a device in the charging path
An auto-backup device — often called a backup cube — sits in the middle of your normal charging setup: wall charger → cube → phone. Your phone still charges exactly as before, but now there is a small computer in the path that can see the connection and act on it.
The Data Backup Cube is the clearest example. It is an MFi-certified adapter with a slot for a microSD card. You plug your charger into the cube and your phone cable into the cube, and from then on charging and backing up happen at the same time.
What happens the moment you plug in
When the phone connects and begins charging, a companion app (iStore Pro on MemoryKept devices) detects the connection and starts copying new photos and videos to the card inside the cube. Here is the sequence:
- You plug your phone into the cube to charge, exactly as you would any night.
- The app recognises the connection and checks which photos and videos are new since the last backup.
- Those new files copy to the microSD card inside the cube while the phone charges.
- When you unplug in the morning, the backup is already done — no app to open, nothing to confirm.
Why it is "incremental" (and why that matters)
The first time you use it, the cube copies your entire existing camera roll, which can take a while depending on how many photos and videos you have. After that, it is incremental: each session only copies what is new since the last backup. A typical night might be a handful of photos, so it finishes in moments.
Incremental backup is what makes the "while charging" model practical. If it re-copied everything every night it would be slow and wasteful; by copying only new files, it stays fast and quietly keeps your backup current without you ever managing it.
Where the photos actually go
On a backup cube, your photos land on a microSD card you insert yourself. The cube has no built-in storage, which is deliberate — it keeps the device inexpensive and lets you pick whatever capacity suits your library, then upgrade later without replacing the cube. When you want to view or move the files, the cube doubles as a standard microSD card reader on a computer.
A photo stick works on the same offline principle but carries its own built-in storage instead. You can read about it on the Multiport Photo Stick page.
Auto backup while charging vs the cloud
Both approaches aim for the same thing — your photos copied somewhere safe without you remembering to do it — but they differ in custody, cost, and where the copy lives. The table sums it up:
| Auto backup while charging | Cloud auto-backup | |
|---|---|---|
| Trigger | Plugging in to charge | Connecting to Wi-Fi / power |
| Where photos go | A card in a device you own | A provider's servers |
| Internet required | No | Yes |
| Ongoing cost | None (you supply the card) | Subscription above the free tier |
| Off-site copy | No — it is local | Yes — survives fire or theft |
| Privacy | Stays in your hands | Held under provider terms |
What makes it reliable on iPhone
For an iPhone, the make-or-break detail is Apple MFi certification. A certified cube uses genuine Apple-licensed connector components, so it keeps working after iOS updates; uncertified clones rely on copied chips that Apple can disable, which is the usual reason a cheap accessory suddenly shows an "accessory not supported" error.
The other half is the app: because it manages detection and the incremental copy, it needs to be maintained by a manufacturer who keeps it current with new iOS releases. Together, a certified adapter and a maintained app are what make auto backup while charging something you can genuinely set and forget.
Frequently asked questions
Does auto backup while charging need Wi-Fi or the internet?▾
No. It runs entirely offline over the physical connection between the phone, the cube, and the memory card. There is no cloud account, subscription, or network involved.
Does it copy all my photos every time I charge?▾
Only the first time. The initial backup copies your whole camera roll; after that it is incremental, copying only the photos and videos added since the previous session, which is why later backups finish quickly.
Where are the photos stored?▾
On a backup cube they are stored on a microSD card you insert yourself — the cube has no built-in storage. That keeps the device cheap and lets you choose your own capacity, and the cube doubles as a card reader on a computer.
Does it work with iPhone and Android?▾
Yes. The Data Backup Cube supports iOS / iPadOS 10.0+, Android 6.0+, and macOS 11.0+. For iPhone it is Apple MFi-certified, so it stays compatible through iOS updates.