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Feature List and Known Issues


The following features are available in Flex:

  • Channels
    • Voice
    • SMS - BETA
    • WebChat - BETA
    • Facebook (no media) - BETA
    • WhatsApp (no media) - BETA
    • Bring your own channel
  • Cold Call Transfer to an agent - BETA
  • Cold Call Transfers to a queue - BETA
  • Warm Call Transfer to an agent - BETA
  • Warm Call Transfers to a queue - BETA
  • PCI Payments
  • Realtime Team Dashboard
  • Call Monitor - BETA
  • Chat monitoring - NEW
  • Single Agent Skilling
  • Historical dashboards and reports
  • Call Recording on/off

Beta features

Items in Beta are ready for broader testing and use. They are offered either publicly or on an invite-only basis.
There are no SLAs provided. Support is provided, but is exempt from support plan guarantees.
Use of beta features in production should be limited to use cases that are not mission-critical. Read more about Twilio Beta Product Support here

Flex Webchat on IE 11

Customer must refresh page to start new chat after previous chat was ended, "Read" receipt rendered on the wrong side, and default link color is very close to the background color on the blue webchat bubble

Handling voice calls

For all voice call tasks, Flex UI sets endConferenceOnExit property on the conference participant dynamically based on the type of the participant and the number of participants in the conference. This property is set dynamically for agent participants and external parties, not customer participant. It is dynamically determined and reset everytime a number of participants changes in the conference.

Call monitoring issues

To guarantee the stability of the call monitoring function, the supervisor must be in an unavailable state to invoke call monitoring.

No multitab support

Out of the box, Flex can only be run in a single tab today. You may experience unstable behaviour with voice calls, if Flex is opened in more than one tab at the same time.

Warm Transfer


  • Warm transfer functionality is available to Flex customers through the TR SDKv2. A public REST API is not available at the moment for transfers.
  • Warm transfer feature is enabled for Tasks that are for Voice channels only
  • Tasks that are transferred cannot be explicitly identified through cumulative or real-time statistics
  • AgentA when transferring to AgentB does not hear a hold music during warm transfer
  • When AgentA transfers to AgentB, AgentA cannot specify a wrap-up reason. Only the last agent handling the task can specify a reason for wrap-up.
  • When AgentA transfers to AgentB directly, transfer will be successful only if AgentB is available and has capacity to take the task.


  • Disposition is done at a task level
  • Missing call-flow report in the standard report set for transfer tracking
  • Missing metrics covering nr. of transfers in the standard metrics set
  • Missing metric of how many transfers an agent is making if an agent was the last one to speak to the customer
  • Missing metric of number of calls transferred to another queue (overflow out)
  • Number of calls to this ACD queue with another queue as original receiver (overflow in)
  • Agent_1 → Agent_2 segments displayed as Customer → Agent2 in reports
  • Can’t determine the order of transfers between queues (originated queue, queue where call was resolved, transfers between queue A and queue B )
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