Synchronize your Nubo calendars and contacts with your smartphone, tablet or computer.

Installation and Setup

First go around the applications installed on your machine to uninstall-or at least disable-all "cloud" services from GAFAM. If you had already started using them (sometimes without your knowledge), make sure that the entire content that was uplinked to it is saved on at least one of your machines. Otherwise make a copy of this content.

Open an account

Create an account at Nubo.
You can create a Nubo account via Komun to enable the cloud service.

It is based on the free Software NextCloud (formerly on OwnCloud).

In Nubo, choose the option "Mobile & Desktop" (see previous chapter) and choose the option you want to use.

Installing synchronization Clients

A "client" is a software that you install on each of your machines so that you can access the server and synchronize the files with it.

On your compatible Android® smartphone/tablet

Download the free NextCloud application for Android® from the F-Droid Store (1) or from the Google Play Store®. It allows the synchronization of the files.

Application settings:
If you want the photos and/or videos you take with your smartphone to be automatically uploaded to Nubo, set the "Automatic uploading" settings.
Only when you are connected to a Wifi network if you want to save your mobile data.
You can also choose to immediately delete the photos/videos from your smartphone: useful if you lack space or for privacy reasons.
You can set an access code to protect access to your cloud when your smartphone is unlocked.

Important: After you set up the contact synchronization, when you create a new contact on your smartphone, choose "Davdroid" as the location.
So not only will the contact be added on the phone but it will also be copied to your cloud (and therefore potentially synchronized with your other machines).

(1) F-Droid is an installable catalogue of FOSS (Free and Open Source Software) applications for the Android platform.

On your iPhone® or iPad® 

Download the NextCloud application for iOS® from the App Store® (requires iOS® version 9.0 or later). It allows the synchronization of the files.

Application settings:
If you want the photos and/or videos you take with your smartphone to be automatically uploaded to Nubo, set the "Automatic uploading" settings.
Only when you are connected to a Wifi network if you want to save your mobile data.
By default these uploads are stored on the cloud in the "Photos" folder. You can also choose to immediately delete the photos/videos from your smartphone: useful if you lack space or for privacy reasons.
There is also an option "upload all photos from the camera" which allows to send to Nubo the photos already present on the device.

You can set an access code to protect access to your cloud when your smartphone is unlocked.

On your computer 

Download the NextCloud application for Windows® or Mac® or GNU/Linux from the official site.
(Remark : if you use Lint Mint 18, follow the instuctions for Ubuntu 16.04.)

It allows the synchronization of files located on your computer, in the NextCloud directory of your personal folder.
Note: You can choose whether to synchronize certain subdirectories (for example, to use them as a backup location, see below).

Synchronizing contacts and calendars with Thunderbird 

You must first install some extensions to Thunderbird:
The Lightning calendar (even if you only want to sync contacts)
Inverse SOGo connector (for synchronization) and CategoryManager (to manage contact groups)
or CardBook (for synchronization)

Synchronizing contacts:

Thunderbird > Addresses > New Remote Address Book > name, URL =
(wher XXXXX is the The digital ID of your Nubo account)

Synchronizing calendars in Lightning:

Thunderbird > Calendar > new calendar > network > CalDAV > place:


Initializing data

Initial setting up of old contacts

From Backup to Nubo

To start you need to recover (export) all your old contacts present on your smartphone in the form of a VCF format file.

Then import these contacts into Nubo using one of the two methods below:

Option 1: Via Thunderbird sync

Step 1: Import the Address Book to. vcf format in Thunderbird

Thunderbird > Addresses > menu Tools > Import > click on Address Book > click on vCard (.vcf)

A new local address book is created, such as "VCF Import".

At this point it is recommended to clean up your contacts and make sure that the information is consistent.

If the phone numbers appear like this: 012-345-6789 the VCF file must be corrected.
The VCF file can be opened in a simple text editor. Remove the dashes by ten "find replace" successively (-0 by 0,-1 and 1...-9 by 9).
You can also put the numbers in international format (replace the initial 0 with + 31) to get: + 31123456789.

Step 2: Create a remote Address Book

See § 1.2.3 for the Procedure. Name it for example "Nubo Sync".

Step 3: Move the imported contacts to the remote address Book

By clicking and dragging move all the contacts from the "VCF Import" file to the "Nubo Sync".

BUG: If the move does not occur, this is a bug related to SOGo connector.Workaround: Disable the SOGo connector module, restart Thunderbird, move and then reactivate SOGo Connector and restart Thunderbird: synchronization will take a few seconds after reboot.

Option 2: via a VCard file transfer (.vcf)

Access Nubo via the web, go to the Contacts application, then open the settings (gear icon at the bottom of the left column), then press the "Import to Contacts" button and choose the VCF file that contains the contacts to import.

A difficulty may arise when transferring contacts to a vcf file: Android 6 and Thunderbird 52 export their contacts in VCard 1.2 format.
While NextCloud (and OwnCloud) import only vcards 3.0 and 4.0.
The formats of the contacts are therefore not compatible.(Note: Contacts exported from Apple are in the Format 3.0.).

Solution: The ' MoreFunctionsForAdressBook ' extension for Thunderbird allows export in VCard v 3.0 format.
To get this format set the preferences of the extension: vcard Format tab, choose VCard 3.0.
Then to export via the extension: Thunderbird > Address Book, right-click > MoreFunctionsForAdressBook > Export > as VCard.

So we export the contacts from the Smartphone (VCard 1.2), we transfer the file to a computer equipped with Thunderbird.
They are imported into Thunderbird (see option 1, Step 1).
Then we export them from Thunderbird via the extension in VCard format 3.0. This last file can then be imported into Nubo.

From Nubo to smartphone and tablet

After all contacts have been saved to the cloud, suspend synchronization on your smartphone if you have enabled it and clear all contacts from your smartphone before restarting a synchronization.This way you will be assured that all the contacts now present on the phone will be synchronized.

Other data

The files (including photos, videos, and notes) in the NextCloud folder on your computer will automatically be upgraded to Nubo during the first synchronization.

Calendar events and tasks already present in your applications on the smartphone will be synchronized to Nubo during the first synchronization.
Check By default older events of more than 90 days are not synchronized.


Use of Synchronization

In general you can opt for automatic synchronisation or to disable the automatism.
Warning: you must disable optimization for both DavDroid and Nextcloud applications.
Despite this in some cases automatic synchronization is not done when applications are closed, if you have this kind of problem it is recommended to leave DavDroid and Nextcloud open permanently, and to re-open them if they have been closed (Or your phone has been restarted).

In any case, you can force the synchronization manually:

  • Android > Contacts, accounts > DavDroid > Account concerned > "Sync now"
  • Nextcloud > map InstantUpload > Sync
  • Thunderbird > Addresses : button "Sync"


For more info, please consult the technical documentation.

Choose the option "Mobile & Desktop" (see the previous chapter for more info) and select the option you want to use.

Contact content

Caution: Not all applications handle contact information in the same way. This should be taken into account when this information is seized.

Contact sort order:

  • On NextCloud 11: By name to be displayed (consisting from the fields: Prefix + First name + middle name + name + suffix)
  • On Thunderbird 52: By name to be displayed (made from: FirstName + LastName). ! Thunderbird does not support the prefix, middle, and suffix fields (appears included in name to display-in case of No name, the suffix is loaded in the Name field)
  • On Android 6: By phonetic name, then by first name + surname or surname + First name (manages the prefix, middle name and suffix fields, but does not take them into account for sorting).

Example: "Voltairine De Cleyre will be sorted alphabetically by letter V or letter C (NextCloud case).

In conclusion, it is not recommended to use the prefix, middle, and suffix fields. It is better to embed these elements in the First Name field (and in the Name field for the suffix). Whether or not to integrate the prefix as you want it or not to intervene in the sort order.

Managing Contact Groups

The groups are managed by: NextCloud, Thunderbird with the extension CategoryManager, application Contacts of some smartphones (eg: Fairphone Open). 
The groups are not managed by: Android Contacts on some smartphones (old version of Android?). In this case you can use the free Simple contacts application available in F-Droid or the Play Store.

Other Difference

Thunderbird does not handle two mobile numbers for the same contact-> make two separate contacts otherwise the second number will be lost.


Notes can be edited on your smartphone using the Notes application.
The notes can be published on the Web page NextCloud > notes.
On the computer the notes are stored in the folder ~/NextCloud/Notes.
These are text files (. txt), they can be opened as such by any editor.


All events synchronize between the Calendar application (for Android), the "Calendar" Application of NextCloud and Lightning (in Thunderbird).


On Smartphones, the NextCloud application does not automatically download Nubo files. To do this you have to open them manually.
By default they are saved in the folder [storage]/Android/Data/com.nexcloud.client/files/

However, manual updates or changes made from the smartphone are synchronized immediately.

Between Nubo and the computer the synchronization is automatic. It is done periodically according to the NextCloud client configuration.

Use the option "External Storage" (see the previous chapter) and add a storage. Yous can choose between Amazon S3, FTP, Nextcloud, Openstack Object storage, SFTP and WebDav.

Photos and videos taken from the Smartphone

You can set the "Automatic uploading" settings in the NextCloud application of your smartphone to immediately (or only when you are connected to Wifi) download the photos and videos taken by your device.

By default the files will be uplinked to the following cloud server folders (from an Android® smartphone):

  • InstantUpload/Camera for the default Camera app
  • InstantUpload/OpenCamera free OpenCamera app
  • InstantUpload/Screenshots the screenshots (for Android : clcik simultaneous on "Volume -" and "Power")

Backup or Synchronization?

Warning: A synchronized folder is not a reliable backup.
If a file is accidentally deleted or corrupted from one of your devices, it will disappear immediately from Nubo (in fact it is placed in the trash, see next) and then all the other devices synchronized.
To have a reliable backup on the server you have to put the files in a folder that is not synchronized.

Delete files

When a file is removed from Nubo (either directly or from a synchronized device), it is placed in the server Recycle Bin ("deleted files") where it can still be retrieved. If the purpose of the operation is to free up space on the server, then delete the file(s) from the Trash. To act on the server Recycle Bin it is necessary to access it via the Web.

What to do in case of theft or loss of one of your machines?

You must immediately disconnect it from Nubo. Connect to your account on Nubo via a Web browser at this address: need to know your username and password-and close the sessions corresponding to the stolen machine.
On NextCloud: Personal Menu > Sessions, menu... > close.


Sharing folders and files

From Nubo (or from your file browser if you have integrated the interaction with the NextCloud client application), you can specify that a specific file (or folder) can be shared with other people.

Public Link

A link is generated that will allow people to whom you send it access to the shared file (or folder).
You can optionally specify a password (to be transmitted by another channel than the one by which you transmit the link!).

Targeted sharing

To an email

You can share the file (or folder) by specifying an email address: The recipient receives an email with a single link to access the shared items.

To another person's Nubo account

You can specify the Nubo ID of the person you want to share your resources with.
For example, this identifier to a "remote" account will be of the form
If you are on the same server as your recipient you just have to indicate its ID (XXXXX) or its nickname.
The person will receive a notification in his or her synchronization application with Nubo.
If it accepts sharing, the folder (or file) will be copied into its own cloud, and therefore synchronized with all of these devices.

If you ignore the person's ID, use the email share: the person will be able to add the share itself to their own cloud.

As attachment to an email

If you want to email a large attachment, you can automatically use your Nubo as a relay.

Requires the Thunderbird mail client with the extension "NextCloud for Filelink".


Deleting Sync

On your Android® compatible device

NextCloud does not automatically download the Nubo files. For automatic uploads of photos and videos you can selectively disable them.
Uninstall NextCloud if necessary.

In the Notes application, delete the server address. or uninstall the application.

In the DAVdroid application: Temporarily disable synchronization (uncheck boxes) or delete the account.

On your computer

Launch the NextCloud synchronization client and uncheck the folders that you no longer want to synchronize. or uncheck the "Start at startup" option and exit the application.

In Thunderbird, disable the SOGo connector (or Cardbook) extension.