Help & Support

FAQ for Handling Handheld Smart Devices for Service Maintenance, Recycling Use, and Disposal

  1. Handling Handheld Smart Devices for Service Maintenance
  1. What should be done before taking your smart phones, pads and tablets for software services?

    • Back up all data first (using iTunes for iOS devices, Android Debug Bridge for Android, or Windows Device Recovery Tool for Windows).
    • Takeout all user-removable storage cards from device.
    • Sign out from all logged on services and accounts, such as email services, cloud storages, wireless LAN, etc., unless they are the software/app having problems.
    • For the sake of data privacy and security, you should allow sufficient time and be present all time while the service provider is checking your device for software problems, especially if the device has been used for handling sensitive information.
  2. What should be done before taking your smart phones, pads and tablets for hardware maintenance?
    For devices that CAN be started up:

    • As the device may need to be left with the hardware service provider for some time, please ensure that all data has been backed up (using iTunes for iOS devices, tool from manufacturer for Android, or Windows Device Recovery Tool for Windows).
    • Sign out from all logged on services and accounts, such as email services, cloud storages, wireless LAN, etc.
    • Uninstall the respective mobile apps and/or de-register the apps, as appropriate.
    • Remove SIM cards of subscribed mobile/communication services from device.
    • Remove user-removable memory cards from device.
    • May consider to factory reset the device (please refer to Section 4); however, must make sure that all data have been backed up for restoring to the device after maintenance.

    For devices that CANNOT be started up:

    If retrieval of data stored in the device is desirable, meaning that the data in the device have not been backed up or synced to host services, e.g. email, storage on cloud, please try the following:

    • First check whether it is simply the battery fault. For device with user-removable battery, if the battery is deformed (e.g. swollen), most likely it malfunctions and don’t ever try to recharge it and dispose of it according to the guideline of the manufacturer.
    • If nothing abnormal is found with the battery or the device (battery cannot be removed) from visual inspection, try to recharge the device/battery for a few hours with the original charger that came with the device or one that is manufacturer approved (not those that claimed to be compatible). Before charging, please check the power outlet (PC USB or wall socket) to ensure that it is functioning, e.g. it has been used to power up other electrical appliance/device, and it should recharge the device/battery if it is not dead.
    • After charging the device/battery for a few hours, if the device still cannot be started up after a few attempts, for device with built-in battery (cannot be removed from the device), please bring the device to the official manufacturer* (not reseller or dealer) to arrange for a repair. For device with user-removable battery, borrow a charged and working battery of exactly the same model to replace the dead battery and try to start up the device and if successful, then replacing the battery will solve the problem. If it still fails after a few attempts, please bring the device to the official manufacturer* (not reseller or dealer) to arrange for a repair.

    After checking the battery, if the device still cannot be started up, and if the device has been used for handling sensitive information and retrieval of data stored in the device is not a must, please consider disposal of the device safely (please refer to Section 6).

    *The official manufacturers are recommended as they will have well documented maintenance and privacy agreements for handling devices that cannot be started up. However, before bringing a dead device to maintenance service, especially one that has been used to handle sensitive information, you should rationalize the consequences of unrecoverable data versus the risk of possible data leakage.

  1. Handling Handheld Smart Devices for Retirement or Recycling Use by Another Person
  1. What should be done before we retire or transfer smart phones, pads and tablets for recycling use by another person?

    • Make sure that the data that need to be retained have been successfully transferred from your old device to your new device, or have been backed up (using iTunes for iOS devices, tool from manufacturer for Android, or Windows Device Recovery Tool for Windows).
    • Sign out from all logged on services and delete all user accounts, such as email services, cloud storages, wireless LAN, etc.
    • Uninstall the respective mobile apps and/or de-register the apps, as appropriate.
    • Remove SIM cards of subscribed mobile/communication services from device.
    • Takeout user-removable storage cards from device. Secure erase these storage cards if appropriate.
    • Make sure that all data contents stored inside a device are erased in such a way that they are unrecoverable (please see Section 4).
  2. What is the meaning of “unrecoverable”? Is factory reset of device sufficient?

  3. According to the manufacturers, factory reset will destroy all data/files/apps stored in a device and will erase all user identities/options/preferences, and then will restore a device to its initial state, as if it has just been unpacked, and is ready for use by another person.

    • iOS devices enabled data encryption by default, and a factory reset will make the data in these devices inaccessible, according to Apple. For steps to perform a factory reset for iOS devices, please refer to:
      What to do before selling or giving away your iPhone, iPad, or iPod touch
      Use iTunes on your Mac or PC to restore your iPhone, iPad, or iPod to factory settings

    • Android** devices do not enable data encryption by default, so performing a factory reset may still leave traces of data in the internal storage; therefore, a user should encrypt the storage first before doing a factory reset for Android devices. The encryption option in most Android devices is under Settings -> Security (may various between brand/model). For steps to perform a factory reset for Android devices, please refer to:

      Reset Android device to factory settings



    • Windows** mobiles devices do not enable data encryption by default, so performing a factory reset may still leave traces of data in the internal storage; therefore, a user should encrypt the storage first before doing a factory reset for Windows mobile devices. The encryption option in most Windows mobiles devices is under Settings -> System -> Device encryption (may various between brand/model). For steps to perform a factory reset for Windows devices, please refer to:
      Reset Windows phone
      Restore or reset Surface

    • **Owing to the diversity of Android and Windows mobile devices, please refer to the respective manufacturer of your device’s brand/model.
  4. More than a factory reset?

  5. The manufacturers’ procedures for a factory reset are well tested and considered safe for average users. The following complex procedures for device wiping may only be needed by expert users.

    • If the factory reset of devices is still considered insufficient, device wiping using the usual backup/restore tool by a user (using iTunes for iOS devices, Android Debug Bridge for Android, or Windows Device Recovery Tool for Windows) to refill the internal memory/storage of a device with dummy data, whereby ensuring that any trace of data which might not have been deleted and erased by the factory reset will overwrite the original data in the device, and then perform a factory reset again.
    • The time required for device wiping will depend on the size of the internal memory/storage of a device, e.g. an iPhone 128GB may take over 2 hours.
    • Device wiping (with different dummy content each time, if desired) can be performed as many times as a user wishes provided that sufficient time is allowed.
  1. Handling Handheld Smart Devices for Disposal
  1. What about devices not intended for recycling use by another person, or unknown devices of which the uses/users cannot be identified, or devices that cannot be started up?

  2. The following is recommended, especially for devices which have been known for handling sensitive information:

    • The internal memory/storage of such devices can be removed from the device and be destroyed, e.g. physically fragmented then disposed of. Alternatively, physically destroy the whole device in the same way.
    • Devices and any removed internal memory/storage must be physically locked up in a drawer or a safe until they are destroyed.
    • Devices with internal memory/storage removed can be considered for go-green recycling as scrap.
  3. What services are provided by the Computing Services Centre (CSC) in recycling use or disposal of handheld smart mobile device?

  4. For devices owned by the University, the CSC can:
    • Provide advice on the factory reset and the wiping of devices. For the sake of data security, such actions have to be performed by the device owner with the on-site assistance of the CSC. Owing to the diversity of device brand/model, the CSC can only provide best-effort support.
    • Perform the removal of internal memory/storage from devices for destroying. Owing to the different brand/model, the CSC will try best effort; however, it may scratch or damage the shell/screen of the devices. For the sake of data security, the removal of internal memory/storage will be done in the presence of the device owner, and the removed memory/storage will be returned to the device owner for destroying. The CSC can also provide reference to external professional service on device disintegrator/shredder.
    • Users can raise a CSC Work Request to initiate a request for the above support.
csc@cityu.edu.hk