# Use Function Keys on the Mobile App

Function keys give you a shortcut to the features you use most. Some keys show you the live status of the object they watch: a Busy Lamp Field (BLF) key, for example, indicates whether a colleague's extension is idle, ringing, or on a call. Other keys fire off an action such as dialing a number or checking voicemail. This page explains how to reach and use function keys from the Cloud Voice App on your mobile device.

## Before you start

Confirm your environment meets these minimums:

- **Phone system**: Firmware version **84.22.0.17** or later.
- **Cloud Voice App (iOS)**: Version **5.23.7** or later.
- **Cloud Voice App (Android)**: Version **5.23.8** or later.

You also need at least one function key already set up. Function keys are defined in the Cloud Voice App web or desktop client, not on the mobile app itself.

## Open the Function Keys panel

1. From the top-right corner of the Cloud Voice App, tap the function keys icon ![Function keys icon](/images/pbx/function-key.png).

   :::note
   If a call is in progress, tap the minimize icon ![Minimize call icon](/images/pbx/narrow.png) to shrink the call screen before you tap the function keys icon.
   :::

   ![Tapping the function keys icon in the top-right corner of the app](/images/pbx/tap-fn.png)

   The **Function Keys** panel opens. It lists every configured key that the mobile app can use. Keys that only work on a physical IP phone are left out.

   ![The Function Keys panel showing the configured keys available on the mobile app](/images/pbx/fn-list.png)

2. Read the monitoring status shown on a key, or tap a key to run the operation it is assigned to.

## Why some function keys don't respond during a call

While you are on a call, a few keys stop performing their normal action. What is blocked depends on the kind of call you are on.

| Call type | What is limited |
|-----------|-----------------|
| One-to-one Cloud Voice App call | Tapping **Speed Dial**, **Check Voicemail**, **Check Group Voicemail**, **Intercom**, or **Boss-Secretary Feature** does nothing. |
| Audio conference or multi-party call | Tapping **BLF**, **Speed Dial**, **Check Voicemail**, **Check Group Voicemail**, **Park & Retrieve**, **Intercom**, or **Boss-Secretary Feature** does nothing. |
| GSM (cellular) call | **DTMF** (dual-tone multi-frequency, the tones a phone sends when you press keypad digits) sends no digits. Other call-related keys such as **BLF**, **Speed Dial**, and **Voicemail** still work: the app carries out the action and automatically places the current GSM call on hold. |

:::caution
On the Android version of the Cloud Voice App, call-related function keys work during a GSM call only when **Allow GSM calls during calling** is turned on. If this setting is off, tapping those keys during a GSM call will not perform the action. You can find the setting under **Your Account > Settings > Advanced**.
:::