During a call, if you need to make an outgoing call while putting the current call on hold:

1. Tap on the ‘More’ icon to switch to the additional features set, and press the ‘Add call’ icon 

More Icon

Add Call Icon

2. Choose а contact that you’d like to call from the list.

i:Numbpad Icon

3. After establishing the connection, you can switch between the two calls by tapping the switch icon (I).

Switch Icon

During a call, if you need to make an outgoing call while putting the current call on hold: 

1. Tap on the ‘Add call’ icon.

Add Call Icon

2. Choose а contact that you’d like to add to a call from the list OR press the numpad icon Choose а contact that you’d like to add to a call from the list.

Numpad Icon

3. After the connection has been established, you can switch between the two calls by tapping on the pause icon.

4. Tap on the Swap Calls Icon to switch between lines.

Swap Calls Icon