The best alternatives to Bitsms are MailerSend, Chain Networking, and Bitwala legacy. If these 3 options don't work for you, we've listed a few more alternatives below.
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AssemblyAI— Speech-to-Text API with superhuman accuracy
MailerSend is a powerful transactional messaging service that gives developers a quick start in setting up transactional email and SMS, while also allowing marketing and design teams to easily contribute without coding skills.
sat2.io is a simple and funny way to introduce Bitcoin to your friends. You can send Satoshis using the Lightning Network. Let your friends discover this new breakthrough in technology and be the one introducing them to Bitcoin.