Every phone rewrites your messages now. None of them tells you what yours says.

Open Messages on a recent iPhone, select what you’ve typed, and tap Writing Tools¹. You get proofreading, a rewrite, and a choice of Friendly, Professional or Concise. It costs nothing and there’s no account to make.

I run a paid app that overlaps with that. So the fair question, and I get asked it in App Store reviews, is why anyone would give me money for something Apple bundles for nothing.

This is my answer.

Two things you should know before you read the rest

The first is obvious: I co-founded Subtext, so I’m not a neutral party. The section called “Where the big ones beat us” exists because a comparison written by a founder is worthless without one.

The second is stranger. Subtext runs on Anthropic’s models, which our privacy policy² names alongside Deepgram for voice and OpenAI for read-aloud. So Claude is simultaneously our supplier and one of the products in this article. We pay a competitor for the engine. That’s a genuinely odd position to be in and I’d rather you heard it from me.

Everything below was checked on 11 August 2026.

What all of them already do, and do well

Before the differences, the honest baseline. Every product in this article can take a message you’ve written and give you back a cleaner version. Grammar, spelling, length, and a formality dial from casual to professional. On that job they range from good to excellent, and several are free.

If that’s what you want, you’re finished. Use what’s on your phone. The rest of this article is about a narrower thing.

The one job none of them takes on

Every one of them answers “make this better”. None of them answers “tell me what this actually says”.

That second question is a different piece of work. It means reading a draft as something a specific person will receive in a specific situation, naming the part that reads as colder or more defensive than you meant, and saying so before you send rather than explaining it afterwards. It means taking a screenshot of the thread, or a five-minute voice note you don’t want to listen to again, and working out what’s really being asked of you.

I don’t think the big companies avoid this because it’s technically hard. I think they avoid it because telling someone their message sounds passive-aggressive is a rude thing for a phone to do.

Platform features can’t afford to be rude to a billion people. A tool you choose on purpose can.

Apple Intelligence: free, everywhere, and deliberately incurious

Apple’s Writing Tools work nearly anywhere you can type, including third-party apps, and have shipped since iOS 18.1 and macOS Sequoia 15.1¹. You get proofread, summarise, and rewrite, with Friendly, Professional and Concise as presets. There’s also a “Describe your change” box³ where you can type something like “make this more enthusiastic” and get it.

That last feature is better than most people realise. It’s an open-ended instruction slot, which means the ceiling is whatever you can articulate.

The catch is the word articulate. Apple will do what you ask. It will not tell you what to ask for. It reads your draft as text to be improved, never as a message that a specific person is about to receive and interpret. Ask it to make something friendlier and it will. It won’t mention that your third sentence reads as a threat.

For most messages that gap doesn’t matter. For the ones you rewrite five times, it’s the whole problem.

Google: two different tools, and neither is the one you’d expect

Google has split this into two products.

Magic Compose⁴ sits inside Google Messages and rewrites your draft into a chosen style, described by Google as a creative partner rather than a grammar check. The styles lean playful, including one that rewrites you as Shakespeare.

Gemini in Google Messages⁵ is the bigger one: a full assistant inside your texting app, free with a personal Google account, now live in more than 165 countries. You need to be 18 or over with RCS turned on. Google also states plainly that chats with Gemini are not end-to-end encrypted⁵, which is worth knowing before you paste a conversation about your marriage into it.

Between them Google covers drafting and rephrasing comfortably. Neither analyses the emotional reading of what you’re about to send.

Samsung: the most complete free package on any phone

Samsung’s Writing Assist⁶ is the one people underrate. It lives in the keyboard toolbar, and since One UI 7 it works with any keyboard rather than only Samsung’s own. You get spelling and grammar, writing style, summarise, bullet points, table, and a Composer that drafts from keywords. Style variants include Professional, Casual, Polite and Emojify, across more than 40 languages.

In early 2026 Samsung confirmed the core Galaxy AI features stay free with no expiry date, after earlier wording suggested they might not.

If you own a recent Galaxy, you already have a more capable writing assistant than most paid apps sell. I say that as someone who sells one.

Grammarly: the closest thing to us at real scale

Grammarly is the only large player that has taken tone seriously as a distinct problem. Its tone detector⁷ has been running since 2019, and Pro flags sentences likely to be misread and offers rewrites before you send. It runs in a browser extension, desktop apps, a mobile keyboard, Google Docs, and it powers the writing assistant inside Samsung’s keyboard.

Free covers grammar, spelling, tone detection and a monthly allowance of AI prompts. Pro is $12 a month billed annually, or $30 month to month⁸. Its parent company renamed itself Superhuman⁹ in October 2025 while keeping the Grammarly product name.

The difference sits somewhere it took me a while to articulate. Grammarly is calibrated for work. Its idea of a bad message is one that’s unclear, unprofessional, or grammatically wrong. That calibration is correct for the email to your manager and wrong for the message to your mother, where the failure modes are different: sounding cold when you meant careful, sounding defensive when you meant hurt, over-explaining because you’re anxious. Those read as fine writing to a work-tuned tool.

Grammarly could add this. If they decide personal messaging is worth the attention, they arrive with a mobile keyboard and tens of millions of users.

ChatGPT and Claude: the ones that can already do everything

Both can do what my app does. That’s not false modesty. Paste your draft, describe the relationship, name the tone you want, ask what could be misread, and you’ll get a good answer. ChatGPT¹⁰ runs a free tier plus Go at $8, Plus at $20, and Pro tiers above that. Claude¹¹ has a free tier with Pro at $20 a month.

So why does a small app survive next to them? Three reasons I can defend.

The instructions are the work. “Paste your draft, describe the relationship, specify the tone, ask what could be misread” is four things to remember at the exact moment you’re least able to think clearly. It’s 11pm and you’re upset. Nobody prompt-engineers at 11pm.

The blank box asks the wrong question. A chat window says “what do you want”. A tool built for one job can ask “who is this going to, and what happened before this message”, which is what actually determines the answer.

They default to agreeing with you. Ask a general assistant whether your angry message is justified and it will usually find a way to say yes, because that’s the shape of a helpful reply to a question phrased that way. The useful answer is often that you’re right and the message will still land badly.

Every one of those is an interface problem rather than a capability one, and interface problems get solved.

Wordtune and DeepL Write: excellent at a different job

Worth a paragraph because people ask. Wordtune¹² does sentence-level rewrites with tone modes, free up to ten rewrites a day, with paid tiers whose prices shift by region. DeepL Write is the best thing available for making non-native English read naturally, with formal, informal, enthusiastic, confident and diplomatic styles.

Both are document tools. Neither reads a conversation, and neither has an opinion about how your message will feel to the person receiving it.

Feature comparison

Y means documented on the company’s own site or support pages. N means it isn’t.

On that last row: our terms say your content is never used to train models, and that our providers may not either². Defaults differ across the others and some ask you to opt out rather than opt in, so check the setting in whatever you use. That’s a two-minute job worth doing once.

What they cost

Where the big ones beat us

They’re free and already there. There’s nothing to download or sign up for, and for most people that settles the question on its own.

They’re in the keyboard. Apple, Samsung and Grammarly work where you’re already typing. We make you paste, share or screenshot. Every time someone tells me the app is great but they forget to open it, they’re describing this.

They handle documents better. Grammarly on a long report, DeepL Write on a second-language email, Wordtune on an essay. We’re built for messages and it shows outside that.

They aren’t going anywhere. Apple and Google will still ship this in five years.

Which one to use when

That last row is the only one I’d argue about. Everything above it, the free tools win or draw, and I’d rather say that than pretend otherwise.

Subtext is for the moment before you send, when you want to know how it reads, what’s easy to misinterpret, and how to say the same thing without the edge you didn’t mean. Screenshot, voice note, or half-finished draft, in fourteen languages, on your phone or in the browser. Free to start.

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If you think I’ve been soft on my own app or unfair to a product you work on, tell me. I’ll fix it and say what changed.

Samet Durgun is the co-founder of Subtext, an app that catches the emotional tone of your messages and rewrites them in your own voice. He’s based in Berlin.

Sources

Every link above goes to the primary source where one exists. Checked on 11 August 2026. Prices and platform features change often, so confirm before you buy.

1. Apple Support, How to use Writing Tools with Apple Intelligence.
2. Subtext, Terms, privacy and your account.
3. Apple Support, Use Writing Tools with Apple Intelligence on iPhone.
4. Android, Using Magic Compose: AI for text messages and writing.
5. Google, Use Gemini in Google Messages.
6. Samsung, Enhance your messages with Writing Assist on your Samsung Galaxy.
7. Grammarly, Writing tone detector and tone suggestions.
8. Grammarly, Pro plans.
9. Grammarly, Grammarly rebrands company as Superhuman.
10. OpenAI, ChatGPT pricing.
11. Anthropic, What is the Pro plan? and Claude plans and pricing.
12. Wordtune, plans and pricing.