DAVDroid calendar and contact sync

There's a very nice Android synchronization client called DAVDroid.
The beauty of this app is that the setup is extremely simple and sets up contact and calendar sync in one step. Here's a quick run through the setup:

1. Install the DAVDroid app and open it.
2. Select URL and user name:

3. Fill in your details:

4. Select the auto detected your address books and calendars you'd like to sync:

Now it's done and you can view the new calendars and address books in the calendar and contacts app!

Connect your website to Group-Office

Often it's desired to connect a website to Group-Office. For example you might want to have a sign up form that adds a contact to Group-Office.
Group-Office has a powerful JSON API to do this. Here's an example script that add's a contact using cURL. With cURL you can do HTTP requests in your own PHP script that you can run on your own CMS like Wordpress or Drupal for example.

<?php
//URL to Group-Office. You must use SSL because we use basic auth!
$groupoffice_url = "https://localhost/groupoffice-6.1/www/";

//Group-Office username and password. You should create a restricted user that 
//can only add contacts to this addressbook.
$username = 'website';
$password = 'secret';

//The contact properties to POST
$post = array(
  'addressbook_id' => 1, //required
  'company_id' => 0,
  'first_name' => 'Curl',
  'last_name' => 'Tester',
  'initials' => '',
  'title' => '',
  'suffix' => '',
  'sex' => 'M', // or 'F"
  'birthday' => '', //local format
   'email' => '',
  'email2' => '',
  'email3' => '',
  'department' => '',
  'function' => '',
  'home_phone' => '',
  'work_phone' => '',
  'fax' => '',
  'work_fax' => '',
  'cellular' => '',
  'cellular2' => '',
  'homepage' => '',
  'country' => 'NL', //2 character ISO code 
  'state' => '',
  'city' => '',
  'zip' => '',
  'address' => '',
  'address_no' => '',
  'comment' => ''
);

$process = curl_init($groupoffice_url . '?r=addressbook/contact/submit');
curl_setopt($process, CURLOPT_USERPWD, $username . ":" . $password);
curl_setopt($process, CURLOPT_POST, 1);
curl_setopt($process, CURLOPT_POSTFIELDS, $post);
curl_setopt($process, CURLOPT_RETURNTRANSFER, TRUE);

$return = curl_exec($process);
curl_close($process);

//JSON decode the response
$json = json_decode($return, true);


//Handle success or error here.
if ($json['success']) {
 echo "Contact saved!\n";
} else {
 echo "Failed to save contact: " . $json['feedback'] . "\n";
}