SMS auto reply, and why it is a different compliance problem

mesej does not send SMS. There is no code path here that takes a phone number and a message on any mobile network, so nothing below is a pitch. The query also splits into two unrelated problems sharing one name.

One is a phone-level feature that already exists on the device in your hand, and Apple documents it well enough to quote. The other is a business sending automatic texts from its own number, which is harder than the WhatsApp equivalent for a reason that is regulatory rather than technical. We are not going to summarise that regulation, and why we will not is the second half of this page.

The phone-level version, which Apple documents

If you want your phone to answer a text while you are driving, that is a built-in iPhone feature with its own Apple support page, stamped March 30, 2026 when we read it. Apple describes the container first:

With iOS 15 and later, the Driving Focus helps you stay focused on the road. When you turn it on, text messages and other notifications are silenced or limited.

The auto reply sits inside it, and Apple is precise about who gets one: “With Auto-Reply, favorites and those you allow notifications from will get an auto reply when you have the Driving Focus on.” The choice is “Select an option, like No One, Recents, Favorites, or All Contacts”, and the text is yours: “From here, you can customize the auto-reply message that people get when they message you while a Driving Focus is on.”

The part to know before relying on it is that the sender can override it.

They can choose to notify you anyway by sending “urgent” as an additional message.

Apple’s iPhone User Guide adds a sentence worth keeping in view: “The Driving Focus is not a substitute for following all the rules that prohibit distracted driving.”

Two limits follow from Apple’s own description rather than from testing. The trigger is driving, not your opening hours, so this is not a business away message wearing a different hat. And the reply goes to contact groups you chose in advance, so a stranger texting your work number is the case it was never built for.

On Android we could not find the same page

Google Messages is Android’s own texting app, and its Help Centre publishes an index of 15 feature articles. We read the whole list on 19 September 2026. None of them is an auto reply. The page promises breadth, “When you use Google Messages, you can do more than just send texts”, and what it documents nearby is the opposite thing: “With Android 7.0 and up, you can schedule messages to send on phones.” A scheduled message is one you wrote and aimed at somebody, not a reaction to an incoming text.

The nearest automation Google does document is hands-free rather than automatic. Android Auto’s messaging page covers voice, “You can send, receive, and listen to text messages through SMS or any messaging app compatible with Android Auto”, and every reply path on it ends with you confirming the send. We also fetched the Google Assistant help article that search results attribute to driving mode. It redirected to the Assistant Help home page, so there is nothing on it to quote and we have not cited it.

A handset maker may ship its own auto reply in its own messaging app. We have not tested those and will not describe them from a vendor’s own summary, so the page to read is your manufacturer’s.

The business version, and the sentence we are not going to write

A business answering texts automatically from its own number is a different product, a different bill and a different rulebook. The rulebook is the hard part, and here is our whole position on it: we are not going to summarise telecoms or consent law. It varies by country, by state or province, by whether a message counts as marketing or transactional, and by which carrier and aggregator sit between you and the recipient. We have not read a primary regulatory source to a standard we would publish, so we will not paraphrase one.

That is a more useful sentence than it looks, because the alternative is to gesture at compliance, name an acronym, cite nothing, and leave you believing a page like this one settled a legal question. Check the rules that apply where you operate, with somebody accountable for the answer.

What we can show without summarising any law is how fragmented the ground is. Google documents the unsubscribe flow for RCS chats with businesses in its own app, and that flow is country-specific:

“Unsubscribe” is available in RCS chats with businesses in Brazil, France, Germany, India, Netherlands, Mexico, Spain, UK, and US.

When you unsubscribe, Google Messages sends a “STOP” message from your phone number to the business. It’s the business’s responsibility to honor your request.

The keyword itself changes with the country. This is Google’s own table:

Country or region	Stop keyword	Start keyword
Germany, India, Netherlands, United Kingdom, United States	STOP	START
Spain, Mexico	BAJA	ALTA
France	STOP	Démarrer
Brazil	parar	começar

Note where the obligation lands. The app sends the word; the business has to honour it. Google adds that “Google Messages doesn’t block future messages” and that after unsubscribing “You may still receive essential, requested messages from them”. Nothing there is enforced by the phone. It is enforced by rules we are not summarising, against a sender the platform does not control.

The identity layer is missing for the same reason. Google’s page for its own verified business channel contrasts it with plain texting: “Unlike text messages that don’t show verification to end users, the chat experience is clearly branded with the company’s name, logo, and a verification check mark.” Even that channel has no single operator, because “Chats are managed by businesses, messaging solution providers, and carriers”, and it is not uniformly available: “Availability of RCS on Android varies by region and carrier.”

Why WhatsApp is the easier problem, and it is not that Meta is more relaxed

The contrast is publishing, not permissiveness. One company writes the rules down in one place and we can quote them, which is the only reason our other pages can be specific.

The feature is described in a sentence: WhatsApp’s Business app features page says the away message will “Respond automatically to messages received outside your business hours to set expectations and let customers know when you’ll be back.” The boundary for anything built on the platform is published too. The Business Messaging Policy states that “You may reply to a user message without use of a Message Template as long as it’s within 24 hours of the last user message”, and Meta’s service messages page states what happens after: “When the window closes, you can only send pre-approved template messages.”

Consent is where the comparison gets honest. Meta requires it, “Businesses are required to obtain opt-in before messaging people on WhatsApp”, then hands the legal test straight back to you: “It is up to businesses to determine the method of opt-in”. So Meta has not solved your compliance problem either. It has written down its own platform rules, which is a smaller thing, and enough of one that a reader can check what we say.

The answer

For a driving auto reply on an iPhone, use Apple’s. It is free, documented, and nobody needs to sell you anything. For a business, the version with published rules is the WhatsApp Business app away message.

For SMS, the first question is not which tool to buy. It is which rules bind you, and that one has to be answered where you operate, by somebody who will stand behind the answer. Treating a vendor page that cites nothing as evidence about the vendor is the same discipline as picking review management software.