Setting up a new phone: transfer data, apps and eSIM safely

In what order should you switch?

The golden rule: your old phone stays as it is until everything works on the new one. Direct transfers of data and eSIM need both devices close together, with the old one unlocked.

What should you prepare on the old phone?

Start with a fresh backup: Apple lists it as the first step before an iPhone changes hands. Germany's Federal Office for Information Security (BSI) recommends checking at least once that the backed-up data is complete. Why syncing is not a backup is explained in Synced or backed up? Understand the difference.

• Update both phones. Quick Start needs iOS 11 or later on the old iPhone.
• Check free storage on the new phone.
• Have the old phone's screen lock and your account password to hand.
• Moving from Android to Android? Turn on WhatsApp backups on the old phone first.
• Getting a new number? Add it as a trusted phone number to your Apple Account beforehand; see also Old phone number on your account? Check your recovery details.

Same system: how do you move from iPhone to iPhone or Android to Android?

iPhone to iPhone with Quick Start

The old iPhone must be connected to Wi-Fi with Bluetooth turned on.

With iCloud, you can use the new iPhone straight away while apps and data download in the background. With a direct transfer, wait until it has finished on both devices.

Android to Android

A new Android phone offers to copy apps and data during setup. Google recommends a cable that fits both phones, but it also works without one. Important: you can only transfer data once, so do it during setup.

According to Google, downloads such as PDFs, apps not from Google Play, data from apps that don't use Android backup, non-Google accounts and ringtones are left behind. Samsung phones also offer their own Smart Switch tool. Because manufacturers adapt Android, labels may differ.

Switching between Android and iPhone: what comes across?

Android to iPhone

The iPhone must not be set up yet; otherwise Apple says you need to erase it first or move content manually. On the Quick Start screen, choose to set up without another Apple device.

Apple lists contacts, message history, photos, calendars, email accounts and WhatsApp content among the things that transfer. Music, books and PDFs have to be moved manually. Don't use other apps or take calls on the Android phone meanwhile.

iPhone to Android

During setup, the new Android phone asks where to copy from: choose “iPhone or iPad”. With a cable, tap “Trust” on the iPhone if prompted and then “Copy” on Android. Wirelessly, the Android Switch app from the App Store helps; it needs iOS 15 or later. Google says paid apps, Safari bookmarks and health data don't transfer. Turn off iMessage on the iPhone before you switch, so texts keep reaching you.

How does your eSIM get onto the new phone?

With an eSIM, your number isn't stored on a card but in a digital profile from your network provider. Whether it can move directly between two phones therefore also depends on the provider. A physical SIM simply moves across.

According to Apple, both iPhones need iOS 18.4 or later, the same Apple Account and Bluetooth, with the old iPhone unlocked. If your provider doesn't support Quick Transfer, it may offer a QR code instead, or you can contact it directly.

Both phones need Android 12 or later and a screen lock. If the transfer fails, Google says the existing device or eSIM can keep working: try again, or ask your provider to activate the eSIM. With iOS 26 or later, some providers and manufacturers support moving an eSIM between Android and iPhone. A separate eSIM for travel is a different matter: see Travel eSIM: compare offers and avoid pitfalls.

How do you protect your number from misuse?

Because an eSIM can be activated immediately on another phone, criminals use it for SIM swapping. Switzerland's National Cyber Security Centre explains that attackers use phished login details for a provider's customer portal to order a new SIM and then receive the victim's text-message codes. Treat eSIM QR codes and your customer account details like a key.

It is normal for the old phone to lose mobile service after your own switch. But if calls and texts stop working on the new phone although it shows reception, the NCSC advises contacting your provider immediately.

When should you erase the old phone?

Only once everything works on the new one: calls, texts, mobile data, photos, contacts, chats, banking and authenticator apps. Anything missing can still be retrieved now.

Before erasing an iPhone, Apple advises backing up again, unpairing your Apple Watch, deregistering iMessage if you are moving to a non-Apple phone, and signing out via Settings › your name › “Sign Out”. Careful: if you delete photos or contacts manually while signed in to iCloud, Apple says they are permanently removed from iCloud and all connected devices. Erasing the whole device, by contrast, does not delete your content from iCloud.

Reset an Android phone following your manufacturer's instructions. The BSI advises choosing the option that deletes content, as some functions only reset settings. For what comes next, see Passing on an old phone: back up first, then sign out properly.

An example: Aoife moves from Android to iPhone

Fictional example: Aoife in Galway has bought an iPhone after years with Android. On Sunday morning she places both charged phones side by side at home on Wi-Fi and starts Move to iOS. While the loading bar runs, she takes no calls. Afterwards she copies her music separately.

For the eSIM, Aoife checks with her provider. That evening she tests calls, texts and her banking app. Only the next day does she reset the old phone with content deletion and take out the memory card.