QuickBlox is a good choice, with APIs and SDKs for building chat and calling into Android, iOS and web apps. It also offers features like embedded chat, voice and video calling, video conferencing, push notifications, data storage and secure file sharing. QuickBlox has certifications for major security standards like SOC2, HIPAA and GDPR, and it's used by companies in health care, finance, e-commerce, social networking and education.
Another option is RingCentral, an all-in-one cloud communications platform that includes phone, message, video and contact center services. It offers business SMS, team messaging, file-sharing, AI-first video meetings and cloud faxing. RingCentral is used by many companies in financial services, health care, education and government, and offers customizable plans for companies of different sizes.
Zoom is another good option, with video meetings, team chat, phone and webinars. It also offers file sharing, VoIP calls, SMS management, virtual event hosting and AI-generated meeting summaries. Zoom has a large developer ecosystem and flexible pricing, making it a good option for companies that want to improve collaboration and productivity.