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Gamma Horizon iOS mobile App user-guide


Gamma Horizon iOS mobile App user-guide

Published: 20/10/2021

Horizon iOS Soft Client User Guide

Minimum System requirements

The iphone is supported on:

      • iPhone 5
      • iPhone 5C
      • iPhone 5S
      • iphone 6
      • iPhone 6+
      • iPhone 7
      • iPhone 7+
      • iPhone 8
      • iPhone X

It will run on iOS 9, iOS 10 & iOS 11

User Account

On Horizon, your user account can be shared across your IP handset, your desktop client and mobile client. This means that if a call is delivered to your user account it will access all clients attached to the service, as well as your IP handset. This allows you to take the call using a device of your choice.

Also if you adjust the call settings for your user account through the client this will be implemented across both your IP handset and the Horizon web interface.

It is important to log out of any client that you do not wish to be contacted on.For example, if you prefer to take calls using your IP handset rather than your desktop, you need to log out of the desktop client. Using Do Not Disturb (DND) will prevent calls coming to your extension across all devices.

Where you need to login to a single account with multiple devices of the same type at the same time (i.e. laptop and desktop using the desktop client, or mobile phone and Tablet using the mobile client) calls will be delivered randomlyto any of the logged-in devices. It is recommended that where the intention is to use multiple devices, users must be logged out of each device when moving between them, so that only one device of each client type is logged-in at any one time.

Number Presentation

Number presentation within the Horizon client mimics that set in the Horizon system. As such, if a user generates a call from the Horizon client, this will output the number presentation assigned to the user's Horizon. account.

An option to hide the number for outbound calls is available within the settings.


The Horizon application can be found within the Apple App Store. Search for Gamma and scroll down to find the Horizon Smartphone App. Click get and the App will download and install.


Signing in

Enter your client username and password. Please note, these are different credentials from the Portal login details.

The password is 35 characters long. It is recommended to copy this from the iphone's email.

You can show the password while you are typing it by tapping the eye icon. You can also set the App to remember the password and sign into the client automatically when your device starts.

You will then be asked a series of questions about accessing your devices contacts and microphone etc. we recommend you accept and then, when asked, set the number for the device, this should be updated with the mobile number of the device.


The main view contains several tabs that present information about the contacts and communications options available as follows:


When you start the soft client for the first time, your contacts list will be empty. There are 2 filter options available along the top of the screen:

iPhone Contacts - These are contacts from your local phone book

Company Directory - These are contacts from a company directory.

The + symbol can be used to add contacts.

making a Call

To make a call to one of your contacts you should tap on their name and then tap the image icon next to the number you would like to call. This will trigger a call to the user via the Horizon platform.

Dial pad

The dial pad allows you to enter a telephone number to be dialled. To dial out enter the number and tap the image button

Pull / retrieve call

Located on the bottom right of the dial pad screen, tapping the imageicon will give two options:

Pull call - Take over a live call from another device.

Retrieve call - Retrieve a parked call


The History tab will show your call log. Using the filters along the bottom you can view all calls, missed calls, received calls or outgoing calls. You can tap the imageto give you the option to delete your call logs.

Standard Features

Settings can be accessed by tapping the image icon in the App's top menu bar. Here you can change some of the initial settings - password remembered / automatic sign-in.

Call Settings

Several settings can be controlled within the App, these settings are synchronised with your account - any changes will impact any other phones or clients you have.

The following settings can be changed:

      • Withhold my number
      • iPhone number
      • Call forward - unreachable
      • call forward - busy
      • Call forward - always
      • Call forward - no answer
      • Do not disturb
      • Call waiting
      • Twinning
      • Remote office

Withhold my number 

To amend tap "Withhold My Number" from the call settings menu and select whether you'd like to enable / disable the feature.

iPhone number

Display and amend the devices mobile number associated to the App.

Call Forwarding - Unreachable

To amend tap "Unreachable" from the Call Forwarding sub menu and select whether you would like to enable  / disable and enter the "forward to" number

Call Forwarding - Busy

To amend tap "Busy" from the call forwarding sub menu and select whether you would like to enable  / disable and enter the "forward to" number

Call Forwarding - Always

To amend tap "Always" from the Call Forwarding sub menu and select whether you would like to enable  / disable and enter the "forward to" number

Call Forwarding - No Answer

To amend tap "No Answer" from the Call Forwarding sub menu and select whether you would like to enable  / disable and enter the "forward to" number

Then set the "Number of Rings" parameter before the call is forward. The App will offer the option to set this parameter up to 20 rings, but Horizon only supports a maximum of 7 rings before diverting the call. If a number higher than 7 is selected you will receive an error message.

Do Not Disturb

To amend tap "Do not disturb" from the call settings menu and select whether you would like to enable/ disable


To amens tap "Twinning" from the settings menu. You will then be presented with a list of "locations" - these are the numbers you would like to twin your Horizon number with.

On the twinning page you can select to activate either all locations - or a combination of one or more as required.

To add a new location tap the "Add Location" then enter a number and description.

If the location is not set to active then it will not be alerted as part of the "Alert All Locations"

The Call Control, Prevent Diverting Calls and Answer Confirmation options are not supported on this version

Remote Office

To amend tap "Remote Office" from the settings menu and select whether you would like to enable / disable and enter the number you'd like to use for Remote Office

Collaborate Bolt-On-Features

Horizon Collaborate is a Unified Communications and Collaboration (UCC) service, offering advanced features, including instant messaging and presence, video, desktop and file sharing, conferencing, mobility and more. Available on Mac, Windows, Android and iOS.

The Collaborate client for iPhone is currently provided in Beta mode.

To log in you will need

      • Your Horizon username
      • Your Horizon client password

Download TestFlight from Horizon Smartphone App (Beta) for iPhone

Once installed open on your iOS device. You will require your Horizon username and password. The link will open the Testflight app and give you the option to install the Horizon beta client.

To delete the Testflight app and restore to the previous Horizon Smartphone App

You will require your Horizon username and password before starting this process, without them you will lose the ability to use the app.

Click on the Testflight app and select the Horizon app - do not select open. Select Stop Testing, you may need to scroll down to see the option and confirm in the pop up window.

Finding your username credentials

Usernames are available from the login screen of all Horizon clients. Users with the Horizon Integrator can view their username by right clicking on the menu tray icon and selecting the Configuration option and selecting Telephony. image

The original welcome emails from Horizon will contain the username and password should you not have them readily available.

To retrieve your original password credentials the new Beta client will provide a password reset link at the logon screen of the App. The link will direct you to a webpage you will need to enter your username and email addresss.

Note: Resetting the client password will log you out of all other Horizon clients and you will need to update them with the new password as well as the Horizon Smartphone App (Beta).

Need further help?

Check out our Support Hub for additional options or call us on 01603 743388.