| N/A | OneSignal’s omnichannel customer engagement platform offers push notifications, email, in-app messages, and SMS. OneSignal’s automated customer Journeys and one-off campaigns allow users to create messaging strategies that convert, inform, and retain audiences, with little to no coding required for setup. | $9 per month |
| N/A | Twilio offers a CPaaS and CCaaS solution, with the combination of its programmable Voice, Video, and Messaging APIs, as well as the Twilio Flex cloud contact center. Additional capabilities include Twilio's Elastic SIP Trunking, as well as API for WhatsApp. | $0 per min per participant |