What are some alternatives?
Twilio - Brings voice and messaging to your web and mobile applications.
Heymarket - The professional way to text message. Your customers are mobile. Heymarket helps you manage those relationships from your smartphone.
Plivo - Plivo's Voice API enables businesses to build Voice apps to reach customers globally in 200+ countries. Try Plivo's Voice API for free. Instant Sign Up.
Agile CRM - Agile CRM (Customer relationship management) features modern CRM with marketing automation, social suite & web analytics, allowing small businesses to sell and market like the Fortune 500.
Bandwidth - Track your Wi-Fi hotspot usage. Zero configuration required. It just works.
Pony Express HQ - Pony Express HQ is an SMS text message marketing for small businesses, real estates, clubs, communities, dispensaries or non-profits. Send and receive text messages and images online with the large group of customers. Group texting app no reply all.