Yes, you can use developer APIs like Twilio, Nexmo or Plivo to create your own SMS application. Carriers have different ways of identifying behavior they dislike in their network - if you're transparent about what you're doing, follow the rules, and get opt-ins from your subscribers you shouldn't have issues.
The specific limits vary based on a number of factors like volume per period, inbound/outbound ratio and so on, but carriers empowered the short code industry (5 or 6 digit phone numbers) to allow mass messaging to happen on terms they're comfortable with. When you create a short code, you specify what they should expect from you and if they approve you get to send 30+ messages per second.
That said, DIY gets complicated very quickly in this space (hence why we built Locent).
If you just want something for personal use, this is easy to setup with SNS on AWS. I've used it to send a text to myself when my favorite snowboarding resort has a favorable snow report.
The specific limits vary based on a number of factors like volume per period, inbound/outbound ratio and so on, but carriers empowered the short code industry (5 or 6 digit phone numbers) to allow mass messaging to happen on terms they're comfortable with. When you create a short code, you specify what they should expect from you and if they approve you get to send 30+ messages per second.
That said, DIY gets complicated very quickly in this space (hence why we built Locent).