# What Iflow does

Iflow is a business SMS service. It sends text messages from your organisation to mobile phones, one at a time or thousands at once, and receives the replies. Iflow has been sending business SMS since 1998 and is run by DiaryBook Limited in Dublin.

## Three ways to send

| Method | Best for |
|--------|----------|
| [Web portal](/docs/sending/web-portal/) | Sending by hand to a person, a group or an uploaded list |
| [Email to SMS](/docs/email-to-sms/send-by-email/) | Staff who work from their inbox, and systems that already send email alerts |
| [DiaryBook API](/docs/api/http-api/) | Your own applications, databases and monitoring tools |
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All three use the same account, the same credit and the same sender IDs.

## Who your message comes from

Each message shows a sender. It can be:

- **A sender ID**: your organisation's name, up to 11 characters, such as `YOURORG`. People see at a glance who the message is from, but they can't reply to it. In Ireland a sender ID must be [registered with ComReg](/docs/sender-ids/register-with-comreg/).
- **A reply number**: a phone number that people can reply to. Replies arrive back in your Iflow account.

See [Sender IDs](/docs/sender-ids/about-sender-ids/) for how to choose.

## What it costs

You pay for each message part sent and each reply received, at the rates for your country, plus a monthly subscription that depends on your [subscription level](/docs/account/subscription-levels/). Current prices are on the [pricing page](/pricing/).

## Related

- [Create an account](/docs/getting-started/create-an-account/)
- [Send your first message](/docs/getting-started/your-first-message/)
- [Sender IDs](/docs/sender-ids/about-sender-ids/)

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Source: https://iflow.net/docs/getting-started/what-is-iflow/